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Network Working Group                                          E. Foudil
Internet-Draft
Intended status: Informational                           Y. Shafranovich
Expires: January 22, 2020                       Nightwatch Cybersecurity
                                                           July 21, 2019


                   A Method for Web Security Policies
                      draft-foudil-securitytxt-07

Abstract

   When security vulnerabilities are discovered by independent security
   researchers, they often lack the channels to report them properly.
   As a result, security vulnerabilities may be left unreported.  This
   document defines a format ("security.txt") to help organizations
   describe the process for security researchers to follow in order to
   report security 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 January 22, 2020.

Copyright Notice

   Copyright (c) 2019 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   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



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   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 and Prior Work . . . . . . . . . . . . . . . .   3
     1.2.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   4
   2.  Note to Readers . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  The Specification . . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  Scope . . . . . . . . . . . . . . . . . . . . . . . . . .   5
     3.2.  Comments  . . . . . . . . . . . . . . . . . . . . . . . .   5
     3.3.  Separate Fields . . . . . . . . . . . . . . . . . . . . .   6
     3.4.  Digital signature . . . . . . . . . . . . . . . . . . . .   6
     3.5.  Field Definitions . . . . . . . . . . . . . . . . . . . .   6
       3.5.1.  Acknowledgments . . . . . . . . . . . . . . . . . . .   6
       3.5.2.  Canonical . . . . . . . . . . . . . . . . . . . . . .   7
       3.5.3.  Contact . . . . . . . . . . . . . . . . . . . . . . .   7
       3.5.4.  Encryption  . . . . . . . . . . . . . . . . . . . . .   7
       3.5.5.  Hiring  . . . . . . . . . . . . . . . . . . . . . . .   8
       3.5.6.  Policy  . . . . . . . . . . . . . . . . . . . . . . .   8
       3.5.7.  Preferred-Languages . . . . . . . . . . . . . . . . .   8
     3.6.  Example of an unsigned "security.txt" file  . . . . . . .   9
     3.7.  Example of a signed "security.txt" file . . . . . . . . .   9
   4.  Location of the security.txt file . . . . . . . . . . . . . .  10
     4.1.  Web-based services  . . . . . . . . . . . . . . . . . . .  10
     4.2.  Filesystems . . . . . . . . . . . . . . . . . . . . . . .  10
     4.3.  Internal hosts  . . . . . . . . . . . . . . . . . . . . .  10
     4.4.  Extensibility . . . . . . . . . . . . . . . . . . . . . .  10
   5.  File Format Description and ABNF Grammar  . . . . . . . . . .  11
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  12
     6.1.  Compromised Files and Redirects . . . . . . . . . . . . .  12
     6.2.  Incorrect or Stale Information  . . . . . . . . . . . . .  13
     6.3.  Intentionally Malformed Files, Resources and Reports  . .  13
     6.4.  No Implied Permission for Testing . . . . . . . . . . . .  13
     6.5.  Multi-user Environments . . . . . . . . . . . . . . . . .  13
     6.6.  Protecting Data in Transit  . . . . . . . . . . . . . . .  14
     6.7.  Spam and Spurious Reports . . . . . . . . . . . . . . . .  14
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  14
     7.1.  Well-Known URIs registry  . . . . . . . . . . . . . . . .  15
     7.2.  Registry for security.txt Header Fields . . . . . . . . .  15
   8.  Contributors  . . . . . . . . . . . . . . . . . . . . . . . .  16
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  17
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  17
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  19
   Appendix A.  Note to Readers  . . . . . . . . . . . . . . . . . .  19
   Appendix B.  Document History . . . . . . . . . . . . . . . . . .  20
     B.1.  Since draft-foudil-securitytxt-00 . . . . . . . . . . . .  20



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     B.2.  Since draft-foudil-securitytxt-01 . . . . . . . . . . . .  20
     B.3.  Since draft-foudil-securitytxt-02 . . . . . . . . . . . .  21
     B.4.  Since draft-foudil-securitytxt-03 . . . . . . . . . . . .  21
     B.5.  Since draft-foudil-securitytxt-04 . . . . . . . . . . . .  21
     B.6.  Since draft-foudil-securitytxt-05 . . . . . . . . . . . .  22
     B.7.  Since draft-foudil-securitytxt-06 . . . . . . . . . . . .  22
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  22

1.  Introduction

1.1.  Motivation and Prior Work

   Many security researchers encounter situations where they are unable
   to report security vulnerabilities to organizations because there is
   no course of action laid out or no way indicated to contact the owner
   of a particular resource.

   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
   policies.

   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 disclosure
   policies and contact information for organizations in order to report
   security vulnerabilities.

   In this document, we define a richer, machine-parsable and more
   extensible way for organizations to communicate information about
   their security disclosure policies, which is not limited to email and
   also allows for additional features such as encryption.  This format
   is designed to help assist with the security disclosure process by
   making it easier for organizations to designate the preferred steps
   for researchers to take when trying to reach out to them with
   security vulnerabilities.







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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 for security researchers to assist in
   disclosing security vulnerabilities.

   The file is named "security.txt", and this file SHOULD be placed
   under the /.well-known/ path ("/.well-known/security.txt") [RFC8615]
   of a domain name or IP address for web properties.  If it is not
   possible to place the security.txt file in the /.well-known/ path or
   setup a redirect, web-based services MAY place the file in the top-
   level path of a given web domain or IP address ("/security.txt") as a
   fallback option (see Section 4.1).

   For web-based services, the file MUST be accessible via the Hypertext
   Transfer Protocol (HTTP) [RFC1945] as a resource of Internet Media
   Type "text/plain" with the default charset parameter set to "utf-8"
   per section 4.1.3 of [RFC2046], and it MUST be served with "https"
   (as per section 2.7.2 of [RFC7230]).  For file systems and version
   control repositories a "security.txt" file SHOULD be placed in the
   root directory of a particular file system or source code project.

   This text file contains multiple directives with different values.
   The "directive" 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].  Directives MUST be case-insensitive (as
   per section 2.3 of [RFC5234]).  The "value" comes after the directive
   ("https://example.com/security") and follows the syntax defined for
   "unstructured" in section 3.2.5 of [RFC5322].

   A "field" MUST always consist of a directive and a value ("Contact:
   https://example.com/security").  A security.txt file can have an



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   unlimited number of fields.  It is important to note that you MUST
   have a separate line for every field.  One MUST NOT chain multiple
   values for a single directive unless it is explicitly defined by that
   particular field.  Unless otherwise indicated in a definition of a
   particular field, any directive MAY appear multiple times.

3.1.  Scope

   A "security.txt" file MUST only apply to the domain 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 or version control
   repository MUST only apply to the folder or repository in which it is
   located, and not to any of its parent or sibling folders, or
   repositories.  However, it will apply to all subfolders.

   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.

   You MAY use one or more comments as descriptive text immediately
   before the field.  Parsers SHOULD associate the comments with the
   respective field.  Only the line most immediately preceding a field
   SHOULD be associated with that field.




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3.3.  Separate Fields

   A separate line is REQUIRED for every new field.  You MUST NOT chain
   everything into a single field unless defined by that field.  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" directive (as per
   Section 3.5.2), thus allowing the digital signature to authenticate
   the location of the file.

   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 directive allows you to link to a page where security
   researchers are recognized for their reports.  The page being linked
   to SHOULD list individuals or organizations that reported security
   vulnerabilities and worked with you to remediate the issue.
   Organizations SHOULD be careful to limit the vulnerability
   information being published in order to prevent future attacks.

   If this directive 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





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3.5.2.  Canonical

   This directive indicates the canonical URI where the security.txt
   file is located, which is usually something like
   "https://example.com/.well-known/security.txt".  If this directive
   indicates a web URL, then it MUST begin with "https://" (as per
   section 2.7.2 of [RFC7230]).  The purpose of this directive is to
   allow a digital signature to be applied to the location of the
   "security.txt" file.

   This directive MUST NOT appear more than once.

   Canonical: https://example.com/.well-known/security.txt

3.5.3.  Contact

   This directive allows you to provide an address that researchers
   SHOULD use for reporting security vulnerabilities.  The value MAY be
   an email address, a phone number and/or a web page with contact
   information.  The "Contact:" directive MUST always be present in a
   security.txt file.  If this directive 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 directive 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: tel:+1-201-555-0123
   Contact: https://example.com/security-contact.html

3.5.4.  Encryption

   This directive allows you to point to an encryption key that security
   researchers SHOULD use for encrypted communication.  You MUST NOT
   directly add your key to the field, instead the value of this field
   MUST be a URI pointing to a location where the key can be retrieved
   from.  If this directive indicates a web URL, then it MUST begin with
   "https://" (as per section 2.7.2 of [RFC7230]).



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   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

   Example of an OpenPGP key being referenced by its fingerprint:

   Encryption: openpgp4fpr:5f2de5521c63a801ab59ccb603d49de44b29100f

3.5.5.  Hiring

   The "Hiring" directive is used for linking to the vendor's security-
   related job positions.  If this directive indicates a web URL, then
   it MUST begin with "https://" (as per section 2.7.2 of [RFC7230]).

   Hiring: https://example.com/jobs.html

3.5.6.  Policy

   This directive allows you to link to where your security policy and/
   or disclosure policy is located.  This can help security researchers
   understand what you are looking for and how to report security
   vulnerabilities.  If this directive indicates a web URL, then it MUST
   begin with "https://" (as per section 2.7.2 of [RFC7230]).

   Example:

   Policy: https://example.com/security-policy.html

3.5.7.  Preferred-Languages

   This directive 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 directive is
   included then at least one value MUST be listed.  The values within
   this set are language tags (as defined in [RFC5646]).  If this
   directive is absent, security researchers MAY assume that English is
   the default 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 directive 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 v1

   [signature]
   -----END PGP SIGNATURE-----



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4.  Location of the security.txt file

4.1.  Web-based services

   Web-based services SHOULD place the security.txt file under the
   /.well-known/ path; e.g. https://example.com/.well-known/security.txt
   as per [RFC8615].  A security.txt file located under the top-level
   path SHOULD either redirect (as per section 6.4 of [RFC7231]) to the
   security.txt file under the /.well-known/ path or be used as a
   fallback if the ".well-known" path cannot be used.

   If retrieval of a "security.txt" file from the top-level path results
   in a redirect (as per section 6.4 of [RFC7231]), the implementors
   MUST NOT follow that redirect if it leads to another domain or
   subdomain but SHOULD follow that redirect within the same domain name
   (but not different subdomain on the same domain).

   The guidance regarding redirects SHOULD NOT apply to the resource
   locations that appear within the file.

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.  Internal hosts

   A "security.txt" file SHOULD be placed in the root directory of an
   internal host.

4.4.  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 directives as defined in Section 7.2.  Any directives registered
   via that process MUST be considered optional.  To encourage
   extensibility and interoperability, implementors MUST ignore any
   fields they do not explicitly support.




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   In general, implementors SHOULD "be conservative in what you do, be
   liberal in what you accept from others" (as per [RFC0793]).

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 [can-field eol] *line (contact-field eol) *line [lang-field eol] *line
                    ; the order of elements is not important

line             =  (field / comment) eol

eol              =  *WSP [CR] LF

field            =  ack-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

lang-tag         =  < Language-Tag from section 2.1 of [RFC5646] >

uri              =  < URI as per [RFC3986] >




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encryption-field =  "Encryption" fs SP uri

hiring-field     =  "Hiring" fs SP uri

policy-field     =  "Policy" fs SP uri

lang-field       =  "Preferred-Languages" fs SP lang-values

lang-values      =  lang-tag *("," [WSP] lang-tag)

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 4.4

6.  Security Considerations

   Implementors SHOULD review this section as well as the security
   considerations section of [RFC8615].

6.1.  Compromised Files and Redirects

   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 digitally sign their
   "security.txt" files (as per Section 3.4), use the canonical
   directive to sign the location of the file (as per Section 3.5.2),
   and regularly monitor the file and the referenced resources to detect
   tampering.

   Security researchers SHOULD check the "security.txt" file including
   verifying the digital signature and checking any available historical
   records before using the information contained in the file.  If
   "security.txt" file looks suspicious or compromised, it SHOULD NOT be
   used.

   To avoid redirect attacks, redirects for these files MUST NOT be
   followed when the file is placed in the top level path if they lead
   to a different domain (as per Section 4.1).





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6.2.  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.

   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.

6.3.  Intentionally Malformed Files, Resources and Reports

   It is possible for attackers to generate 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 and malformed
   files.  ABNF grammar (as defined in Section 5) SHOULD be used as a
   way to verify these files.

   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.

6.4.  No Implied Permission for Testing

   The presence of a security.txt file can be interpreted by researchers
   as providing permission to do security testing against that asset.
   This can lead to increased testing against an organization by
   researchers.  On the other hand, a decision not to publish a
   security.txt file can 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 can lead to
   pushback against researchers reporting security issues to that
   organization.

   Therefore, implementors MUST NOT assume that presence or absence of a
   "security.txt" file grants or denies permission for security testing.
   Any such permission MAY be defined in a security or disclosure policy
   (as per Section 3.5.6) or a new directive (as per Section 4.4).

6.5.  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 to ensure no third-party



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   can create a page with the "security.txt" AND "/.well-known/
   security.txt" names.

6.6.  Protecting Data in Transit

   To protect a "security.txt" file from being tampered with in transit,
   implementors MUST use HTTPS when serving the file itself and any web
   URLs referenced in it (except as noted in this specification).
   Implementors MUST also perform the correct TLS verification (as per
   [RFC6125]).

   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.

   However, the determination of validity of keys being used is out of
   scope for this specification.  Implementors MUST establish other
   secure means to verify these keys.

6.7.  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.

   Organizations SHOULD weigh the advantages of publishing this file
   versus the possible disadvantages and increased resources required to
   triage security reports.

   Security researchers SHOULD consult the organization's policy, if
   available, 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].






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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 Header Fields

   IANA is requested to create the "security.txt Header Fields" registry
   in accordance with [RFC8126].  This registry will contain header
   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 section 4.5 of [RFC8126].
   Any new field thus registered is considered optional by this
   specification unless a new version of this specification is
   published.

   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

   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 historic: The field is no longer in
       current use

   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:







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   Field Name: Acknowledgments
   Description: link to page where security researchers are recognized
   Multiple Appearances: Yes
   Published in: this document
   Status: current

   Field Name: Canonical
   Description: canonical URL for this file
   Multiple Appearances: No
   Published in: this document
   Status: current

   Field Name: Contact
   Description: contact information to use for reporting vulnerabilities
   Multiple Appearances: Yes
   Published in: this document
   Status: current

   Field Name: Encryption
   Description: link to a key to be used for encrypted communication
   Multiple Appearances: Yes
   Published in: this document
   Status: current

   Field Name: Hiring
   Description: link to the vendor's security-related job positions
   Multiple Appearances: Yes
   Published in: this document
   Status: current

   Field Name: Policy
   Description: link to security policy page
   Multiple Appearances: Yes
   Published in: this document
   Status: current

   Field Name: Preferred-Languages
   Description: list of preferred languages for security reports
   Multiple Appearances: No
   Published in: this document
   Status: current

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.



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   The authors would also like to acknowledge the feedback provided by
   multiple members of IETF's SAAG and SEC-DISPATCH lists.

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>.

   [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>.

   [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>.




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   [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>.

   [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>.

   [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>.






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9.2.  Informative References

   [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





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Appendix B.  Document History

      *Note to the RFC Editor:* Please remove this section prior to
      publication.

B.1.  Since draft-foudil-securitytxt-00

   o  Moved to use IETF's markdown tools for draft updates

   o  Added table of contents and a fuller list of references

   o  Moved file to .well-known URI and added IANA registration (#3)

   o  Added extensibility with an IANA registry for fields (#34)

   o  Added text explaining relationship to RFC 2142 / security@ email
      address (#25)

   o  Scope expanded to include internal hosts, domains, IP addresses
      and file systems

   o  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

   o  Added appendix with pointer to Github and document history

   o  Added external signature file to the well known URI registry (#59)

   o  Added policy field (#53)

   o  Added diagram explaining the location of the file on public vs.
      internal systems

   o  Added recommendation that external signature files should use
      HTTPS (#55)

   o  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






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B.3.  Since draft-foudil-securitytxt-02

   o  Use "mailto" and "tel" (#62)

   o  Fix typo in the "Example" section (#64)

   o  Clarified that the root directory is a fallback option (#72)

   o  Defined content-type for the response (#68)

   o  Clarify the scope of the security.txt file (#69)

   o  Cleaning up text based on the NITS tools suggestions (#82)

   o  Added clarification for newline values

   o  Clarified the encryption field language, added examples of DNS-
      stored encryption keys (#28 and #94)

   o  Added "Hiring" field

B.4.  Since draft-foudil-securitytxt-03

   o  Added "Hiring" field to the registry section

   o  Added an encryption example using a PGP fingerprint (#107)

   o  Added reference to the mailing list (#111)

   o  Added a section referencing related work (#113)

   o  Fixes for idnits (#82)

   o  Changing some references to informative instead of normative

   o  Adding "Permission" field (#30)

   o  Fixing remaining ABNF issues (#83)

   o  Additional editorial changes and edits

B.5.  Since draft-foudil-securitytxt-04

   o  Addressing IETF feedback (#118)

   o  Case sensitivity clarification (#127)

   o  Syntax fixes (#133, #135 and #136)



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   o  Removed permission directive (#30)

   o  Removed signature directive and switched to inline signatures (#93
      and #128)

   o  Adding canonical directive (#100)

   o  Text and ABNF grammar improvements plus ABNF changes for comments
      (#123)

   o  Changed ".security.txt" to "security.txt" to be consistent

B.6.  Since draft-foudil-securitytxt-05

   o  Changing HTTPS to MUST (#55)

   o  Adding language recommending encryption for email reports (#134)

   o  Added language handling redirects (#143)

   o  Expanded security considerations section and fixed typos (#30,
      #73, #103, #112)

B.7.  Since draft-foudil-securitytxt-06

   o  Fixed ABNF grammar for non-chainable directives (#150)

   o  Clarified ABNF grammar (#152)

   o  Clarified redirect logic (#143)

   o  Clarified comments (#158)

   o  Updated references and template for well-known URI to RFC 8615

   o  Fixed nits from the IETF validator

   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






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   Yakov Shafranovich
   Nightwatch Cybersecurity

   Email: yakov+ietf@nightwatchcybersecurity.com















































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