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Network Working Group E. Foudil
Internet-Draft
Intended status: Informational Y. Shafranovich
Expires: 24 February 2021 Nightwatch Cybersecurity
23 August 2020
A File Format to Aid in Security Vulnerability Disclosure
draft-foudil-securitytxt-10
Abstract
When security vulnerabilities are discovered by researchers, proper
reporting channels are often lacking. As a result, vulnerabilities
may be left unreported. This document defines a format
("security.txt") to help organizations describe their vulnerability
disclosure practices to make it easier for researchers to report
vulnerabilities.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 24 February 2021.
Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Simplified BSD License text
as described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Motivation, Prior Work and Scope . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. Note to Readers . . . . . . . . . . . . . . . . . . . . . . . 4
3. The Specification . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Scope of the File . . . . . . . . . . . . . . . . . . . . 5
3.2. Comments . . . . . . . . . . . . . . . . . . . . . . . . 6
3.3. Line Separator . . . . . . . . . . . . . . . . . . . . . 6
3.4. Digital signature . . . . . . . . . . . . . . . . . . . . 6
3.5. Field Definitions . . . . . . . . . . . . . . . . . . . . 7
3.5.1. Acknowledgments . . . . . . . . . . . . . . . . . . . 7
3.5.2. Canonical . . . . . . . . . . . . . . . . . . . . . . 7
3.5.3. Contact . . . . . . . . . . . . . . . . . . . . . . . 8
3.5.4. Encryption . . . . . . . . . . . . . . . . . . . . . 8
3.5.5. Expires . . . . . . . . . . . . . . . . . . . . . . . 9
3.5.6. Hiring . . . . . . . . . . . . . . . . . . . . . . . 9
3.5.7. Policy . . . . . . . . . . . . . . . . . . . . . . . 9
3.5.8. Preferred-Languages . . . . . . . . . . . . . . . . . 9
3.6. Example of an unsigned "security.txt" file . . . . . . . 10
3.7. Example of a signed "security.txt" file . . . . . . . . . 10
4. Location of the security.txt file . . . . . . . . . . . . . . 11
4.1. Web-based services . . . . . . . . . . . . . . . . . . . 11
4.2. Filesystems . . . . . . . . . . . . . . . . . . . . . . . 11
4.3. Extensibility . . . . . . . . . . . . . . . . . . . . . . 11
5. File Format Description and ABNF Grammar . . . . . . . . . . 12
6. Security Considerations . . . . . . . . . . . . . . . . . . . 13
6.1. Compromised Files and Incident Response . . . . . . . . . 13
6.2. Redirects . . . . . . . . . . . . . . . . . . . . . . . . 14
6.3. Incorrect or Stale Information . . . . . . . . . . . . . 14
6.4. Intentionally Malformed Files, Resources and Reports . . 14
6.5. No Implied Permission for Testing . . . . . . . . . . . . 15
6.6. Multi-user Environments . . . . . . . . . . . . . . . . . 15
6.7. Protecting Data in Transit . . . . . . . . . . . . . . . 15
6.8. Spam and Spurious Reports . . . . . . . . . . . . . . . . 16
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
7.1. Well-Known URIs registry . . . . . . . . . . . . . . . . 17
7.2. Registry for security.txt Fields . . . . . . . . . . . . 17
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8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 19
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 19
9.1. Normative References . . . . . . . . . . . . . . . . . . 19
9.2. Informative References . . . . . . . . . . . . . . . . . 21
Appendix A. Note to Readers . . . . . . . . . . . . . . . . . . 22
Appendix B. Document History . . . . . . . . . . . . . . . . . . 22
B.1. Since draft-foudil-securitytxt-00 . . . . . . . . . . . . 23
B.2. Since draft-foudil-securitytxt-01 . . . . . . . . . . . . 23
B.3. Since draft-foudil-securitytxt-02 . . . . . . . . . . . . 23
B.4. Since draft-foudil-securitytxt-03 . . . . . . . . . . . . 24
B.5. Since draft-foudil-securitytxt-04 . . . . . . . . . . . . 24
B.6. Since draft-foudil-securitytxt-05 . . . . . . . . . . . . 25
B.7. Since draft-foudil-securitytxt-06 . . . . . . . . . . . . 25
B.8. Since draft-foudil-securitytxt-07 . . . . . . . . . . . . 25
B.9. Since draft-foudil-securitytxt-08 . . . . . . . . . . . . 26
B.10. Since draft-foudil-securitytxt-09 . . . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 26
1. Introduction
1.1. Motivation, Prior Work and Scope
Many security researchers encounter situations where they are unable
to report security vulnerabilities to organizations because there are
no reporting channels to contact the owner of a particular resource
and no information available about the vulnerability disclosure
practices of such owner.
As per section 4 of [RFC2142], there is an existing convention of
using the <SECURITY@domain> email address for communications
regarding security vulnerabilities. That convention provides only a
single, email-based channel of communication for security
vulnerabilities per domain, and does not provide a way for domain
owners to publish information about their security disclosure
practices.
There are also contact conventions prescribed for Internet Service
Providers (ISPs) in section 2 of [RFC3013], for Computer Security
Incident Response Teams (CSIRTs) in section 3.2 of [RFC2350] and for
site operators in section 5.2 of [RFC2196]. As per [RFC7485], there
is also contact information provided by Regional Internet Registries
(RIRs) and domain registries for owners of IP addresses, autonomous
system numbers (ASNs), and domain names. However, none of these
address the issue of how security researchers can locate contact
information and vulnerability disclosure practices for organizations
in order to report vulnerabilities.
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In this document, we define a richer and more extensible way for
organizations to communicate information about their security
disclosure practices and ways to contact them. Other details of
vulnerability disclosure are outside the scope of this document.
Readers are encouraged to consult other documents such as
[ISO.29147.2018] or [CERT.CVD].
As per [CERT.CVD], "vulnerability response" refers to reports of
product vulnerabilities which is related but distinct from reports of
network intrusions and compromised websites ("incident response").
The mechanism defined in this document is intended to be used for the
former ("vulnerability response"). If implementors want to utilize
this mechanism for incident response, they should be aware of
additional security considerations discussed in Section 6.1.
The "security.txt" file is intended to be complementary and not as a
substitute or replacement for other public resources maintained by
organizations regarding their security disclosure practices.
1.2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
2. Note to Readers
*Note to the RFC Editor:* Please remove this section prior to
publication.
Development of this draft takes place on Github at:
https://github.com/securitytxt/security-txt
3. The Specification
This document defines a text file to be placed in a known location
that provides information about the vulnerability disclosure
practices of a particular organization. This is intended to help
security researchers when disclosing security vulnerabilities.
By convention, the file is named "security.txt".
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When made available on HTTP servers, it MUST be placed under the
/.well-known/ path (as "/.well-known/security.txt") [RFC8615] of a
domain name or IP address. For legacy compatibility, a security.txt
file might be placed at the top level path (see Section 4.1). For
file systems a "security.txt" file SHOULD be placed in the root
directory of the file system.
On HTTP servers, the file MUST be accessed via HTTP 1.0 or a higher
version and the "https" scheme (as per [RFC1945] and section 2.7.2 of
[RFC7230]). It MUST have a Content-Type of "text/plain" with the
default charset parameter set to "utf-8" (as per section 4.1.3 of
[RFC2046]).
This text file contains multiple fields with different values. A
field contains a "name" which is the first part of a field all the
way up to the colon ("Contact:") and follows the syntax defined for
"field-name" in section 3.6.8 of [RFC5322]. Field names are case-
insensitive (as per section 2.3 of [RFC5234]). The "value" comes
after the field name ("https://example.com/security") and follows the
syntax defined for "unstructured" in section 3.2.5 of [RFC5322]. The
file may also contain blank lines.
A "field" MUST always consist of a name and a value ("Contact:
https://example.com/security"). A security.txt file can have an
unlimited number of fields. It is important to note that each field
MUST appear on its own line. Unless specified otherwise by the field
definition, multiple values MUST NOT be chained together for a single
field. Unless otherwise indicated in a definition of a particular
field, any field MAY appear multiple times.
Implementors should be aware that some of the fields may contain URIs
using percent-encoding (as per section 2.1 of [RFC3986]).
3.1. Scope of the File
For HTTP servers, a "security.txt" file MUST only apply to the domain
or IP address in the URI used to retrieve it, not to any of its
subdomains or parent domains.
A "security.txt" file that is found in a file system MUST only apply
to the folder in which it is located and that folder's subfolders.
The file does not apply to any of the folder's parent or sibling
folders.
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A "security.txt" file MAY also apply to products and services
provided by the organization publishing the file. Implementors
SHOULD use the policy directive (as per Section 3.5.7) to provide
additional details regarding scope and details of their vulnerability
disclosure process.
Some examples appear below:
# The following only applies to example.com.
https://example.com/.well-known/security.txt
# This only applies to subdomain.example.com.
https://subdomain.example.com/.well-known/security.txt
# This security.txt file applies to IPv4 address of 192.0.2.0.
https://192.0.2.0/.well-known/security.txt
# This security.txt file applies to IPv6 address of 2001:db8:8:4::2.
https://[2001:db8:8:4::2]/.well-known/security.txt
# This file applies to the /example/folder1 directory and subfolders.
/example/folder1/security.txt
3.2. Comments
Any line beginning with the "#" (%x30) symbol MUST be interpreted as
a comment. The content of the comment may contain any ASCII or
Unicode characters in the %x21-7E and %x80-FFFFF ranges plus the tab
(%x09) and space (%x20) characters.
Example:
# This is a comment.
3.3. Line Separator
Every line MUST end either with a carriage return and line feed
characters (CRLF / %x0D %x0A) or just a line feed character (LF /
%x0A).
3.4. Digital signature
It is RECOMMENDED that a security.txt file be digitally signed using
an OpenPGP cleartext signature as described in section 7 of
[RFC4880]. When digital signatures are used, it is also RECOMMENDED
that implementors use the "Canonical" field (as per Section 3.5.2),
thus allowing the digital signature to authenticate the location of
the file.
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When it comes to verifying the key used to generate the signature, it
is always the security researcher's responsibility to make sure the
key being used is indeed one they trust.
3.5. Field Definitions
3.5.1. Acknowledgments
This field indicates a link to a page where security researchers are
recognized for their reports. The page being referenced should list
individuals or organizations that reported security vulnerabilities
and collaborated to remediate them. Organizations should be careful
to limit the vulnerability information being published in order to
prevent future attacks.
If this field indicates a web URL, then it MUST begin with "https://"
(as per section 2.7.2 of [RFC7230]).
Example:
Acknowledgments: https://example.com/hall-of-fame.html
Example security acknowledgments page:
We would like to thank the following researchers:
(2017-04-15) Frank Denis - Reflected cross-site scripting
(2017-01-02) Alice Quinn - SQL injection
(2016-12-24) John Buchner - Stored cross-site scripting
(2016-06-10) Anna Richmond - A server configuration issue
3.5.2. Canonical
This field indicates the canonical URIs where the security.txt file
is located, which is usually something like
"https://example.com/.well-known/security.txt". If this field
indicates a web URL, then it MUST begin with "https://" (as per
section 2.7.2 of [RFC7230]). The purpose of this field is to allow a
digital signature to be applied to the locations of the
"security.txt" file.
Canonical: https://www.example.com/.well-known/security.txt
Canonical: https://someserver.example.com/.well-known/security.txt
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3.5.3. Contact
This field indicates an address that researchers should use for
reporting security vulnerabilities such as an email address, a phone
number and/or a web page with contact information. The "Contact"
field MUST always be present in a security.txt file. If this field
indicates a web URL, then it MUST begin with "https://" (as per
section 2.7.2 of [RFC7230]). Security email addresses should use the
conventions defined in section 4 of [RFC2142].
The value MUST follow the URI syntax described in [RFC3986]. This
means that "mailto" and "tel" URI schemes must be used when
specifying email addresses and telephone numbers, as defined in
[RFC6068] and [RFC3966]. When the value of this field is an email
address, it is RECOMMENDED that encryption be used (as per
Section 3.5.4).
The precedence SHOULD be in listed order. The first field is the
preferred method of contact. In the example below, the email address
is the preferred method of contact.
Contact: mailto:security@example.com
Contact: mailto:security%2Buri%2Bencoded@example.com
Contact: tel:+1-201-555-0123
Contact: https://example.com/security-contact.html
3.5.4. Encryption
This field indicates an encryption key that security researchers
should use for encrypted communication. Keys MUST NOT appear in this
field - instead the value of this field MUST be a URI pointing to a
location where the key can be retrieved. If this field indicates a
web URL, then it MUST begin with "https://" (as per section 2.7.2 of
[RFC7230]).
When it comes to verifying the authenticity of the key, it is always
the security researcher's responsibility to make sure the key being
specified is indeed one they trust. Researchers must not assume that
this key is used to generate the digital signature referenced in
Section 3.4.
Example of an OpenPGP key available from a web server:
Encryption: https://example.com/pgp-key.txt
Example of an OpenPGP key available from an OPENPGPKEY DNS record:
Encryption: dns:5d2d37ab76d47d36._openpgpkey.example.com?type=OPENPGPKEY
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Example of an OpenPGP key being referenced by its fingerprint:
Encryption: openpgp4fpr:5f2de5521c63a801ab59ccb603d49de44b29100f
3.5.5. Expires
This field indicates the date and time after which the data contained
in the "security.txt" file is considered stale and should not be used
(as per Section 6.3). The value of this field follows the format
defined in section 3.3 of [RFC5322]. It is RECOMMENDED that the
value of this field be less than a year into the future to avoid
staleness.
This field MUST always be present and MUST NOT appear more than once.
Expires: Thu, 31 Dec 2020 18:37:07 -0800
3.5.6. Hiring
The "Hiring" field is used for linking to the vendor's security-
related job positions. If this field indicates a web URL, then it
MUST begin with "https://" (as per section 2.7.2 of [RFC7230]).
Hiring: https://example.com/jobs.html
3.5.7. Policy
This field indicates a link to where the vulnerability disclosure
policy is located. This can help security researchers understand the
organization's vulnerability reporting practices. If this field
indicates a web URL, then it MUST begin with "https://" (as per
section 2.7.2 of [RFC7230]).
Example:
Policy: https://example.com/disclosure-policy.html
3.5.8. Preferred-Languages
This field can be used to indicate a set of natural languages that
are preferred when submitting security reports. This set MAY list
multiple values, separated by commas. If this field is included then
at least one value MUST be listed. The values within this set are
language tags (as defined in [RFC5646]). If this field is absent,
security researchers may assume that English is the language to be
used (as per section 4.5 of [RFC2277]).
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The order in which they appear MUST NOT be interpreted as an
indication of priority - rather these MUST be interpreted as all
being of equal priority.
This field MUST NOT appear more than once.
Example (English, Spanish and French):
Preferred-Languages: en, es, fr
3.6. Example of an unsigned "security.txt" file
# Our security address
Contact: mailto:security@example.com
# Our OpenPGP key
Encryption: https://example.com/pgp-key.txt
# Our security policy
Policy: https://example.com/security-policy.html
# Our security acknowledgments page
Acknowledgments: https://example.com/hall-of-fame.html
3.7. Example of a signed "security.txt" file
----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256
# Canonical URL
Canonical: https://example.com/.well-known/security.txt
# Our security address
Contact: mailto:security@example.com
# Our OpenPGP key
Encryption: https://example.com/pgp-key.txt
# Our security policy
Policy: https://example.com/security-policy.html
# Our security acknowledgments page
Acknowledgments: https://example.com/hall-of-fame.html
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.2
[signature]
-----END PGP SIGNATURE-----
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4. Location of the security.txt file
4.1. Web-based services
Web-based services MUST place the security.txt file under the
"/.well-known/" path; e.g. https://example.com/.well-known/
security.txt as per [RFC8615]. For legacy compatibility, a
security.txt file might be placed at the top-level path or redirect
(as per section 6.4 of [RFC7231]) to the security.txt file under the
"/.well-known/" path. If a "security.txt" file is present in both
locations, the one in the "/.well-known/" path MUST be used.
Retrieval of "security.txt" files and resources indicated within such
files may result in a redirect (as per section 6.4 of [RFC7231]).
Researchers should perform additional triage (as per Section 6.2) to
make sure these redirects are not malicious or pointing to resources
controlled by an attacker.
4.2. Filesystems
File systems SHOULD place the "security.txt" file under the root
directory; e.g., "/security.txt", "C:\security.txt".
Example file system:
/example-directory-1/
/example-directory-2/
/example-directory-3/
/example-file
/security.txt
4.3. Extensibility
Like many other formats and protocols, this format may need to be
extended over time to fit the ever-changing landscape of the
Internet. Therefore, extensibility is provided via an IANA registry
for fields as defined in Section 7.2. Any fields registered via that
process MUST be considered optional. To encourage extensibility and
interoperability, implementors MUST ignore any fields they do not
explicitly support.
In general, implementors should "be conservative in what you do, be
liberal in what you accept from others" (as per [RFC0793]).
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5. File Format Description and ABNF Grammar
The expected file format of the security.txt file is plain text (MIME
type "text/plain") as defined in section 4.1.3 of [RFC2046] and is
encoded using UTF-8 [RFC3629] in Net-Unicode form [RFC5198].
The following is an ABNF definition of the security.txt format, using
the conventions defined in [RFC5234].
body = signed / unsigned
signed = sign-header unsigned sign-footer
sign-header = < headers and line from section 7 of [RFC4880] >
sign-footer = < OpenPGP signature from section 7 of [RFC4880] >
unsigned = *line (contact-field eol)
*line (expires-field eol)
*line [lang-field eol] *line
; order of fields within the file is not important
line = [ (field / comment) ] eol
eol = *WSP [CR] LF
field = ack-field /
can-field /
contact-field /
encryption-field /
hiring-field /
policy-field /
ext-field
fs = ":"
comment = "#" *(WSP / VCHAR / %x80-FFFFF)
ack-field = "Acknowledgments" fs SP uri
can-field = "Canonical" fs SP uri
contact-field = "Contact" fs SP uri
expires-field = "Expires" fs SP date-time
encryption-field = "Encryption" fs SP uri
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hiring-field = "Hiring" fs SP uri
lang-field = "Preferred-Languages" fs SP lang-values
policy-field = "Policy" fs SP uri
date-time = < imported from section 3.3 of [RFC5322] >
lang-tag = < Language-Tag from section 2.1 of [RFC5646] >
lang-values = lang-tag *(*WSP "," *WSP lang-tag)
uri = < URI as per [RFC3986] >
ext-field = field-name fs SP unstructured
field-name = < imported from section 3.6.8 of [RFC5322] >
unstructured = < imported from section 3.2.5 of [RFC5322] >
"ext-field" refers to extension fields, which are discussed in
Section 4.3
6. Security Considerations
In addition to the security considerations of [RFC8615], the
following considerations apply.
6.1. Compromised Files and Incident Response
An attacker that has compromised a website is able to compromise the
"security.txt" file as well or setup a redirect to their own site.
This can result in security reports not being received by the
organization or sent to the attacker.
To protect against this, organizations should use the "Canonical"
field to indicate the locations of the file (as per Section 3.5.2),
digitally sign their "security.txt" files (as per Section 3.4), and
regularly monitor the file and the referenced resources to detect
tampering.
Security researchers should triage the "security.txt" file including
verifying the digital signature and checking any available historical
records before using the information contained in the file. If the
"security.txt" file looks suspicious or compromised, it should not be
used.
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While it is not recommended, implementors may choose to use the
information published within a "security.txt" file for incident
response. In such cases, extreme caution should be taken before
trusting such information, since it may have been compromised by an
attacker. Implementors should use additional methods to verify such
data including out of band verification of the PGP signature, DNS-
based approaches, etc.
6.2. Redirects
When retrieving the file and any resources referenced in the file,
researchers should record any redirects since they can lead to a
different domain or IP address controlled by an attacker. Further
inspections of such redirects is recommended before using the
information contained within the file.
6.3. Incorrect or Stale Information
If information and resources referenced in a "security.txt" file are
incorrect or not kept up to date, this can result in security reports
not being received by the organization or sent to incorrect contacts,
thus exposing possible security issues to third parties. Not having
a security.txt file may be preferable to having stale information in
this file. Organizations must use the "Expires" field (see
Section 3.5.5) to indicate to researchers when the data in the file
is no longer valid.
Organizations should ensure that information in this file and any
referenced resources such as web pages, email addresses, and
telephone numbers are kept current, are accessible, controlled by the
organization, and are kept secure.
6.4. Intentionally Malformed Files, Resources and Reports
It is possible for compromised or malicious sites to create files
that are extraordinarily large or otherwise malformed in an attempt
to discover or exploit weaknesses in parsing code. Implementors
should make sure that any such code is robust against large or
malformed files and fields and may choose not to parse files larger
than 32 KBs, having fields longer than 2,048 characters or containing
more than 1,000 lines. The ABNF grammar (as defined in Section 5)
can also be used as a way to verify these files.
The same concerns apply to any other resources referenced within
security.txt files, as well as any security reports received as a
result of publishing this file. Such resources and reports may be
hostile, malformed or malicious.
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6.5. No Implied Permission for Testing
The presence of a security.txt file might be interpreted by
researchers as providing permission to do security testing against
that asset. This might result in increased testing against an
organization by researchers. On the other hand, a decision not to
publish a security.txt file might be interpreted by the organization
operating that website to be a way to signal to researchers that
permission to test that particular site or project is denied. This
might result in pushback against researchers reporting security
issues to that organization.
Therefore, implementors shouldn't assume that presence or absence of
a "security.txt" file grants or denies permission for security
testing. Any such permission may be indicated in the company's
vulnerability disclosure policy (as per Section 3.5.7) or a new field
(as per Section 4.3).
6.6. Multi-user Environments
In multi-user / multi-tenant environments, it may possible for a user
to take over the location of the "security.txt" file. Organizations
should reserve the "security.txt" namespace at the root to ensure no
third-party can create a page with the "security.txt" AND "/.well-
known/security.txt" names.
6.7. Protecting Data in Transit
To protect a "security.txt" file from being tampered with in transit,
implementors should use HTTPS (as per [RFC2818]) when serving the
file itself and for retrieval of any web URLs referenced in it
(except when otherwise noted in this specification). As part of the
TLS handshake, implementors should validate the provided X.509
certificate in accordance with [RFC6125] and the following
considerations:
* Matching is performed only against the DNS-ID identifiers.
* DNS domain names in server certificates MAY contain the wildcard
character '*' as the complete left-most label within the
identifier.
The certificate may also be checked for revocation via the Online
Certificate Status Protocol (OCSP) [RFC6960], certificate revocation
lists (CRLs), or similar mechanisms.
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In cases where the "security.txt" file cannot be served via HTTPS
(such as a filesystem or localhost) or is being served with an
invalid certificate, additional human triage is recommended since the
contents may have been modified while in transit.
As an additional layer of protection, it is also recommended that
organizations digitally sign their "security.txt" file with OpenPGP
(as per Section 3.4). Also, to protect security reports from being
tampered with or observed while in transit, organizations should
specify encryption keys (as per Section 3.5.4) unless HTTPS is being
used for report submission.
However, the determination of validity of such keys is out of scope
for this specification. Security researchers need to establish other
secure means to verify them.
6.8. Spam and Spurious Reports
Similar to concerns in [RFC2142], denial of service attacks via spam
reports would become easier once a "security.txt" file is published
by an organization. In addition, there is an increased likelihood of
reports being sent in an automated fashion and/or as result of
automated scans without human triage. Attackers can also use this
file as a way to spam unrelated third parties by listing their
resources and/or contact information.
Organizations need to weigh the advantages of publishing this file
versus the possible disadvantages and increased resources required to
triage security reports.
Security researchers should review all information within the
"security.txt" file before submitting reports in an automated fashion
or as resulting from automated scans.
7. IANA Considerations
example.com is used in this document following the uses indicated in
[RFC2606].
192.0.2.0 and 2001:db8:8:4::2 are used in this document following the
uses indicated in [RFC6890].
Implementors should be aware that any resources referenced within a
security.txt file MUST NOT point to the Well-Known URIs namespace
unless they are registered with IANA (as per [RFC8615]).
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7.1. Well-Known URIs registry
The "Well-Known URIs" registry should be updated with the following
additional values (using the template from [RFC8615]):
URI suffix: security.txt
Change controller: IETF
Specification document(s): this document
Status: permanent
7.2. Registry for security.txt Fields
IANA is requested to create the "security.txt Fields" registry in
accordance with [RFC8126]. This registry will contain fields for use
in security.txt files, defined by this specification.
New registrations or updates MUST be published in accordance with the
"Expert Review" guidelines as described in sections 4.5 and 5 of
[RFC8126]. Any new field thus registered is considered optional by
this specification unless a new version of this specification is
published.
Designated Experts are expected to check whether a proposed
registration or update makes sense in the context of industry
accepted vulnerability disclosure processes such as [ISO.29147.2018]
and [CERT.CVD], and provides value to organizations and researchers
using this format.
New registrations and updates MUST contain the following information:
1. Name of the field being registered or updated
2. Short description of the field
3. Whether the field can appear more than once
4. The document in which the specification of the field is published
(if available)
5. New or updated status, which MUST be one of:
* current: The field is in current use
* deprecated: The field is in current use, but its use is
discouraged
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* historic: The field is no longer in current use
6. Change controller
An update may make a notation on an existing registration indicating
that a registered field is historical or deprecated if appropriate.
The initial registry contains these values:
Field Name: Acknowledgments
Description: link to page where security researchers are recognized
Multiple Appearances: Yes
Published in: this document
Status: current
Change controller: IESG
Field Name: Canonical
Description: canonical URL for this file
Multiple Appearances: No
Published in: this document
Status: current
Change controller: IESG
Field Name: Contact
Description: contact information to use for reporting vulnerabilities
Multiple Appearances: Yes
Published in: this document
Status: current
Change controller: IESG
Field Name: Expires
Description: date and time after which this file is considered stale
Multiple Appearances: No
Published in: this document
Status: current
Change controller: IESG
Field Name: Encryption
Description: link to a key to be used for encrypted communication
Multiple Appearances: Yes
Published in: this document
Status: current
Change controller: IESG
Field Name: Hiring
Description: link to the vendor's security-related job positions
Multiple Appearances: Yes
Published in: this document
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Status: current
Change controller: IESG
Field Name: Policy
Description: link to security policy page
Multiple Appearances: Yes
Published in: this document
Status: current
Change controller: IESG
Field Name: Preferred-Languages
Description: list of preferred languages for security reports
Multiple Appearances: No
Published in: this document
Status: current
Change controller: IESG
8. Contributors
The authors would like to acknowledge the help provided during the
development of this document by Tom Hudson, Jobert Abma, Gerben
Janssen van Doorn, Austin Heap, Stephane Bortzmeyer, Max Smith,
Eduardo Vela, and Krzysztof Kotowicz.
The authors would also like to acknowledge the feedback provided by
multiple members of IETF's LAST CALL, SAAG, and SECDISPATCH lists.
Yakov would like to also thank L.T.S. (for everything).
9. References
9.1. Normative References
[RFC1945] Berners-Lee, T., Fielding, R., and H. Frystyk, "Hypertext
Transfer Protocol -- HTTP/1.0", RFC 1945,
DOI 10.17487/RFC1945, May 1996,
<https://www.rfc-editor.org/info/rfc1945>.
[RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part Two: Media Types", RFC 2046,
DOI 10.17487/RFC2046, November 1996,
<https://www.rfc-editor.org/info/rfc2046>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
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[RFC2142] Crocker, D., "Mailbox Names for Common Services, Roles and
Functions", RFC 2142, DOI 10.17487/RFC2142, May 1997,
<https://www.rfc-editor.org/info/rfc2142>.
[RFC2277] Alvestrand, H., "IETF Policy on Character Sets and
Languages", BCP 18, RFC 2277, DOI 10.17487/RFC2277,
January 1998, <https://www.rfc-editor.org/info/rfc2277>.
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818,
DOI 10.17487/RFC2818, May 2000,
<https://www.rfc-editor.org/info/rfc2818>.
[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
10646", STD 63, RFC 3629, DOI 10.17487/RFC3629, November
2003, <https://www.rfc-editor.org/info/rfc3629>.
[RFC3966] Schulzrinne, H., "The tel URI for Telephone Numbers",
RFC 3966, DOI 10.17487/RFC3966, December 2004,
<https://www.rfc-editor.org/info/rfc3966>.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, DOI 10.17487/RFC3986, January 2005,
<https://www.rfc-editor.org/info/rfc3986>.
[RFC4880] Callas, J., Donnerhacke, L., Finney, H., Shaw, D., and R.
Thayer, "OpenPGP Message Format", RFC 4880,
DOI 10.17487/RFC4880, November 2007,
<https://www.rfc-editor.org/info/rfc4880>.
[RFC5198] Klensin, J. and M. Padlipsky, "Unicode Format for Network
Interchange", RFC 5198, DOI 10.17487/RFC5198, March 2008,
<https://www.rfc-editor.org/info/rfc5198>.
[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234,
DOI 10.17487/RFC5234, January 2008,
<https://www.rfc-editor.org/info/rfc5234>.
[RFC5322] Resnick, P., Ed., "Internet Message Format", RFC 5322,
DOI 10.17487/RFC5322, October 2008,
<https://www.rfc-editor.org/info/rfc5322>.
[RFC5646] Phillips, A., Ed. and M. Davis, Ed., "Tags for Identifying
Languages", BCP 47, RFC 5646, DOI 10.17487/RFC5646,
September 2009, <https://www.rfc-editor.org/info/rfc5646>.
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[RFC6068] Duerst, M., Masinter, L., and J. Zawinski, "The 'mailto'
URI Scheme", RFC 6068, DOI 10.17487/RFC6068, October 2010,
<https://www.rfc-editor.org/info/rfc6068>.
[RFC6125] Saint-Andre, P. and J. Hodges, "Representation and
Verification of Domain-Based Application Service Identity
within Internet Public Key Infrastructure Using X.509
(PKIX) Certificates in the Context of Transport Layer
Security (TLS)", RFC 6125, DOI 10.17487/RFC6125, March
2011, <https://www.rfc-editor.org/info/rfc6125>.
[RFC6960] Santesson, S., Myers, M., Ankney, R., Malpani, A.,
Galperin, S., and C. Adams, "X.509 Internet Public Key
Infrastructure Online Certificate Status Protocol - OCSP",
RFC 6960, DOI 10.17487/RFC6960, June 2013,
<https://www.rfc-editor.org/info/rfc6960>.
[RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Message Syntax and Routing",
RFC 7230, DOI 10.17487/RFC7230, June 2014,
<https://www.rfc-editor.org/info/rfc7230>.
[RFC7231] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
DOI 10.17487/RFC7231, June 2014,
<https://www.rfc-editor.org/info/rfc7231>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8615] Nottingham, M., "Well-Known Uniform Resource Identifiers
(URIs)", RFC 8615, DOI 10.17487/RFC8615, May 2019,
<https://www.rfc-editor.org/info/rfc8615>.
9.2. Informative References
[CERT.CVD] Software Engineering Institute, Carnegie Mellon
University, "The CERT Guide to Coordinated Vulnerability
Disclosure (CMU/SEI-2017-SR-022)", 2017.
[ISO.29147.2018]
International Organization for Standardization (ISO),
"ISO/IEC 29147:2018, Information technology -- Security
techniques -- Vulnerability disclosure", 2018.
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[RFC0793] Postel, J., "Transmission Control Protocol", STD 7,
RFC 793, DOI 10.17487/RFC0793, September 1981,
<https://www.rfc-editor.org/info/rfc793>.
[RFC2196] Fraser, B., "Site Security Handbook", FYI 8, RFC 2196,
DOI 10.17487/RFC2196, September 1997,
<https://www.rfc-editor.org/info/rfc2196>.
[RFC2350] Brownlee, N. and E. Guttman, "Expectations for Computer
Security Incident Response", BCP 21, RFC 2350,
DOI 10.17487/RFC2350, June 1998,
<https://www.rfc-editor.org/info/rfc2350>.
[RFC2606] Eastlake 3rd, D. and A. Panitz, "Reserved Top Level DNS
Names", BCP 32, RFC 2606, DOI 10.17487/RFC2606, June 1999,
<https://www.rfc-editor.org/info/rfc2606>.
[RFC3013] Killalea, T., "Recommended Internet Service Provider
Security Services and Procedures", BCP 46, RFC 3013,
DOI 10.17487/RFC3013, November 2000,
<https://www.rfc-editor.org/info/rfc3013>.
[RFC6890] Cotton, M., Vegoda, L., Bonica, R., Ed., and B. Haberman,
"Special-Purpose IP Address Registries", BCP 153,
RFC 6890, DOI 10.17487/RFC6890, April 2013,
<https://www.rfc-editor.org/info/rfc6890>.
[RFC7485] Zhou, L., Kong, N., Shen, S., Sheng, S., and A. Servin,
"Inventory and Analysis of WHOIS Registration Objects",
RFC 7485, DOI 10.17487/RFC7485, March 2015,
<https://www.rfc-editor.org/info/rfc7485>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
Appendix A. Note to Readers
*Note to the RFC Editor:* Please remove this section prior to
publication.
Development of this draft takes place on Github at
https://github.com/securitytxt/security-txt
Appendix B. Document History
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*Note to the RFC Editor:* Please remove this section prior to
publication.
B.1. Since draft-foudil-securitytxt-00
* Moved to use IETF's markdown tools for draft updates
* Added table of contents and a fuller list of references
* Moved file to .well-known URI and added IANA registration (#3)
* Added extensibility with an IANA registry for fields (#34)
* Added text explaining relationship to RFC 2142 / security@ email
address (#25)
* Scope expanded to include internal hosts, domains, IP addresses
and file systems
* Support for digital signatures added (#19)
The full list of changes can be viewed via the IETF document tracker:
https://tools.ietf.org/html/draft-foudil-securitytxt-01
B.2. Since draft-foudil-securitytxt-01
* Added appendix with pointer to Github and document history
* Added external signature file to the well known URI registry (#59)
* Added policy field (#53)
* Added diagram explaining the location of the file on public vs.
internal systems
* Added recommendation that external signature files should use
HTTPS (#55)
* Added recommendation that organizations should monitor their
security.txt files (#14)
The full list of changes can be viewed via the IETF document tracker:
https://tools.ietf.org/html/draft-foudil-securitytxt-02
B.3. Since draft-foudil-securitytxt-02
* Use "mailto" and "tel" (#62)
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* Fix typo in the "Example" section (#64)
* Clarified that the root directory is a fallback option (#72)
* Defined content-type for the response (#68)
* Clarify the scope of the security.txt file (#69)
* Cleaning up text based on the NITS tools suggestions (#82)
* Added clarification for newline values
* Clarified the encryption field language, added examples of DNS-
stored encryption keys (#28 and #94)
* Added "Hiring" field
B.4. Since draft-foudil-securitytxt-03
* Added "Hiring" field to the registry section
* Added an encryption example using a PGP fingerprint (#107)
* Added reference to the mailing list (#111)
* Added a section referencing related work (#113)
* Fixes for idnits (#82)
* Changing some references to informative instead of normative
* Adding "Permission" field (#30)
* Fixing remaining ABNF issues (#83)
* Additional editorial changes and edits
B.5. Since draft-foudil-securitytxt-04
* Addressing IETF feedback (#118)
* Case sensitivity clarification (#127)
* Syntax fixes (#133, #135 and #136)
* Removed permission field (#30)
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* Removed signature field and switched to inline signatures (#93 and
#128)
* Adding canonical field (#100)
* Text and ABNF grammar improvements plus ABNF changes for comments
(#123)
* Changed ".security.txt" to "security.txt" to be consistent
B.6. Since draft-foudil-securitytxt-05
* Changing HTTPS to MUST (#55)
* Adding language recommending encryption for email reports (#134)
* Added language handling redirects (#143)
* Expanded security considerations section and fixed typos (#30,
#73, #103, #112)
B.7. Since draft-foudil-securitytxt-06
* Fixed ABNF grammar for non-chainable fields (#150)
* Clarified ABNF grammar (#152)
* Clarified redirect logic (#143)
* Clarified comments (#158)
* Updated references and template for well-known URI to RFC 8615
* Fixed nits from the IETF validator
B.8. Since draft-foudil-securitytxt-07
* Addressing AD feedback (#165)
* Fix for ABNF grammar in lang-values (#164)
* Fixing idnits warnings
* Adding guidance for designated experts
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B.9. Since draft-foudil-securitytxt-08
* Added language and example regarding URI encoding (#176)
* Add "Expires" field (#181)
* Changed language from "directive" to "field" (#182)
* Addressing last call feedback (#179, #180 and #183)
* Clarifying order of fields (#174)
* Revert comment/field association (#158)
B.10. Since draft-foudil-securitytxt-09
* Adjust ABNF to allow blank lines between directives (#191)
* Make "Expires" field required (#190)
* Adding a warning about the well-known URI namespace (#188)
* Adding scope language around products/services (#185)
* Addressing last call feedback (#189)
Full list of changes can be viewed via the IETF document tracker:
https://tools.ietf.org/html/draft-foudil-securitytxt
Authors' Addresses
Edwin Foudil
Email: contact@edoverflow.com
Yakov Shafranovich
Nightwatch Cybersecurity
Email: yakov+ietf@nightwatchcybersecurity.com
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