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Internet Engineering Task Force J. Livingood
Internet-Draft N. Mody
Intended status: Informational M. O'Reirdan
Expires: January 7, 2010 Comcast
July 6, 2009
Recommendations for the Remediation of Bots in Large ISP Networks
draft-oreirdan-mody-bot-remediation-00
Status of this Memo
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Abstract
This document contains recommendations on how large Internet Service
Providers (ISPs) can manage the effects of large numbers of bot
infected computers used by their subscribers via various remediation
techniques. At the time that this document was published, computers
infected by bots and the users of those computers comprise a
substantial number of users for large ISPs. Those Internet users are
exposed to risks such as loss of personal data, increased
susceptibility to online fraud and/or phishing, and becoming an
inadvertent participant in or component of an online crime, spam,
and/or phishing network. Mitigating the effects of and remediating
the installations of bots affecting large numbers of Internet users
will make it more difficult for bot nets to operate and could reduce
the level of online crime on the Internet in general and/or on a
particular ISP's network.
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Table of Contents
1. Requirements Language . . . . . . . . . . . . . . . . . . . . 4
2. Key Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
3. Introduction and Problem Statement . . . . . . . . . . . . . . 5
4. Important Notice of Limitations . . . . . . . . . . . . . . . 6
5. Detection, Notification and Remediation . . . . . . . . . . . 7
5.1. Detection of Bots . . . . . . . . . . . . . . . . . . . . 7
5.2. Notification to Internet Users . . . . . . . . . . . . . . 9
5.3. Remediation of Bot Infected Machines . . . . . . . . . . . 13
5.4. Guided Remediation Process . . . . . . . . . . . . . . . . 14
6. Security Considerations . . . . . . . . . . . . . . . . . . . 15
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 16
9. Normative References . . . . . . . . . . . . . . . . . . . . . 16
Appendix A. Document Change Log . . . . . . . . . . . . . . . . . 16
Appendix B. Open Issues . . . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17
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1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
2. Key Terminology
This section defines the key terms used in this document.
2.1. Bots
A "bot" (derived from the word "robot") refers to a program that is
surreptitiously installed on a system in order to enable that system
to automatically (or semi-automatically) perform a task or set of
tasks typically under the command and control of a remote
administrator, or "bot master." Bots are also known as "zombies."
It is important to note that there are 'good' bots. Such benign bots
are often found in such environments such as gaming and Internet
Relay Chat (IRC) [RFC1459], where a continual, interactive presence
can be a requirement for participating in the games, interacting with
a computing resource, or other purposes. However, for the purposes
of this document, all mention of bots should assume that the bots
involved are malicious in nature. Such malicious bots shall
generally be assumed to have been deployed without the permission or
conscious understanding of a particular Internet user. Thus, without
a user's knowledge, bots may transform the user's computing device
into a platform from which malicious activities are conducted.
2.2. Bot Networks, or Bot Nets
These are defined as concerted networks of bots capable of acting on
instructions generated remotely. The malicious activities are either
focused on the information on the local machine or acting to provide
services for remote machines. Bots are highly customizable so they
can be programmed to do many things. The major malicious activities
include: identity theft, spam, denial of service attacks, key-
logging, fraudulent DNS, proxy services, hosting and click fraud.
Infection vectors include un-patched operating systems, software
vulnerabilities, weak/non-existent passwords, malicious websites, un-
patched browsers, malware and social engineering techniques to gain
access to the user's computer. The detection and destruction of bots
is an ongoing issue and also a constant battle between anti-virus
developers and bot developers. Initially botnets utilized IRC to
communicate but were easy to shutdown if the command and control
server was identified and deactivated. However, with the
introduction of P2P, HTTP and other technologies including
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encryption, bots are considerably more difficult to identify. As a
result increased reliance is being placed on behavioral analysis both
locally and remotely to identify bots.
2.3. Computer
A computer, as used in the context of this document, is intended to
encompass the various personal computing devices used by Internet
users. This may include devices ranging from so-called personal
computers, including laptops, desktops, and netbooks, as well as
mobile phones, smart phones, home gateway devices, and other end user
computing devices which are connected or can connect to the public
Internet and/or private IP networks.
2.4. Malware
This is short for "malicious software." In this case, malicious bots
are considered a subset of malware, which could also include viruses
and other similar types of software. Internet users can sometimes
cause their computer to be infected with malware, which may include a
bot or cause a bot to install itself, via inadvertently accessing a
specific website, downloading a specific file, or other activities.
3. Introduction and Problem Statement
Computers used by Internet users, which in this case are customers of
an Internet Service Provider (ISP), can be infected with malware
which may contain and/or install one or more bots on a computer.
This can present a major problem for an ISP for a number of reasons
(not to mention, of course, the problems created for users). First,
these bots can be used to send spam, in some cases very large volumes
of spam. This spam can result in extra cost for the ISPs in terms of
wasted network, server, and/or personnel resources, among many other
potential costs or side effects. Such spam can also negatively
affect the reputation of the ISP, their customers, and the email
reputation of the IP address space used by the ISP (often referred to
simply as "IP reputation").
In addition, these bots can act as platform for directing,
participating in, or otherwise conducting attacks on critical
Internet infrastructure. Bots are frequently used as part of
concerted Distributed Denial of Service (DDoS) attacks for criminal,
political, anarchistic, or other motivations. For example, bots have
been used to attack Internet resources and infrastructure ranging
from web sites, to email servers and DNS servers, as well as the
critical Internet infrastructure of entire countries.
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While any computing device, including computers used by Internet
users to the servers operated by ISPs and other organizations can be
infected with bots, the majority of bot infections affect the
computers used by Internet users. ISPs have a unique potential role
when it comes to detecting botnets because they provide IP
connectivity for the "good" and "bad" traffic coming from user
systems. Furthermore, ISPs may also be in a unique position to be
able to communicate to Internet users which are their customers, when
customers computers may have been determined to have been or possibly
have been infected with one or more bots.
From an end user perspective, knowing that their computer has been
infected with one or more bots of very important information. Once
they know this, they can take steps to remove the bot, protect
themselves in the future, and resolve any problems which may stem
from the bot infection. Given that bots can not only drain their
local computing and network resources, but also enable the theft of
personal information (including personal financial information), it
is important to help users identify when they may have been infected
with a bot.
As a result, the intent of this document is to provide a guide to
ISPs and other organizations for the remediation of these computers
infected with bots, so as to reduce the size of bot nets and minimize
the potential harm that bots can inflict upon Internet infrastructure
generally, as well as on individual Internet users. Efforts by ISPs
and other organizations could therefore, over time, reduce the pool
of computers infected with bots on the Internet, which in turn could
result in smaller bot nets with less capability for disruption.
4. Important Notice of Limitations
The techniques described in this document in no way guarantee the
remediation of all bots. Bot removal is potentially a task requiring
specialized knowledge, skills and tools, and may be beyond the
ability of average users. Attempts at bot removal may frequently be
unsuccessful, or only partially successful, and may leave a user's
system in an unstable and unsatisfactory state or even still
infected. Attempts at bot removal can also result in side effects
ranging from a loss of data or other files, all the way through
partial or complete loss of system usability.
In general, the only way a user can be sure they have removed some of
today's increasingly sophisticated malware is by "nuking-and-paving"
the system: reformatting the drive, reinstalling the operating system
and applications (including all patches) from scratch, and then
restoring user files from a clean backup.
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5. Detection, Notification and Remediation
The potential mitigation of bots is accomplished through a process of
detection, notification to Internet users, and remediation of that
bot with a variety of tools.
5.1. Detection of Bots
An ISP must first identify that an Internet user, in this case a user
that is assumed to be their customer or otherwise connected to the
ISP's network, is determined to be infected, or likely to have been
infected with a bot. The ISP should attempt to detect the presence
of bots using methods, processes, and tools which maintain the
privacy of the personally identifiable information of their
customers. The ISP also should not block legitimate traffic in the
course of bot detection, and should instead employ detection methods,
tools, and processes which seek to be non-disruptive, as well as
transparent to both Internet users as well as the people who are
deploying and/or operating bot nets.
Detection methods, tools, and processes may include things such as
analysis of specific network and/or application traffic flows (such
as traffic to an email server), analysis of aggregate network and/or
application traffic data, data feeds received from other ISPs and
organizations (such as lists of the ISP's IP addresses which have
been reported to have sent spam), feedback from the ISP's customers
or other Internet users, as well as a wide variety of other
possibilities. It is likely that a combination of all of the
multiple bot detection data points will prove to be the most
effective approach, in order to corroborate information of varying
dependability or consistency, as well as to avoid or minimize the
possibility of false positive identification of computers. Detection
should also, where possible and feasible, attempt to classify a bot
in order to confirm that it is malicious in nature, estimate the
variety and severity of threats it may pose (such as spam bot, key
logging bot, file distribution bot, etc.), and to determine a
potential methods for eventual remediation.
Detection is also time-sensitive. If complex analysis is required
and multiple confirmations are needed to confirm a bot is indeed
present, then it is possible that the bot will do its damage before
it can be stopped. This may mean that an ISP may need to balance the
desire or need to definitively classify and/or confirm a bot, which
may take an extended period of time, with the ability to predict the
strong likelihood of a bot in a very short period of time. This also
means that Internet users may benefit from the deployment of client-
based software protections or other software tools, which can enable
rapid performance of heuristically-based detection bot activity, such
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as the detection of a bot as it starts to communicate a bot net and
execute some type of command. Any bot detection systems should also
be capable of learning and adapting, either via manual intervention
or automatically, in order to cope with a rapidly evolving threat.
As noted above, detection methods, tools, and processes should ensure
that privacy of customers' personally identifiable information is
maintained. While bot detection methods, tools, and processes are
similar to spam and virus defenses deployed by the ISP for the
benefits of their customers (and may be directly related to those
defenses), attempts to detect bots should take into account the need
of an ISP to take care to ensure that such personally identifiable
information is properly protected. Finally, depending upon the
geographic region within which an ISP operates, certain methods
relating to bot detection may need to be included in relevant terms
of service documents or other documents which are available to the
customers of a particular ISP.
There are several bot detection methods, tools, and processes that an
ISP may choose to utilize, as noted in the list below. It is
important to note that the technical solutions available are
relatively immature, and are likely to change over time, and to
evolve rapidly in the coming years. While these items are described
in relation to ISPs, they may also be applicable to organizations
operating other networks, such as campus networks and enterprise
networks.
a. Where legally permissible or otherwise an industry accepted
practice in a particular market region, an ISP may in some manner
"scan" their IP space in order to detect un-patched or otherwise
vulnerable hosts. This may provide the ISP with the opportunity
to easily identify Internet users who appear to already be or are
at great risk of being infected with a bot. Such scanning should
be an unobtrusive and non-disruptive to users and user computers
as possible, using tools which such as NMAP
(http://www.nmap.org), Nessus (http://www.nessus.org), etc.
b. An ISP may also communicate and share selected data, via feedback
loops or other mechanisms, with various third parties. Feedback
loops are consistently formatted feeds of real-time (or nearly
real-time) abuse reports offered by threat data clearinghouses,
security alert organizations, ISPs, and other organizations. The
data may include, but is not limited to, lists of the IP
addresses computers which have or are likely to have a bot
running, domain names or fully qualified domain names (FQDNs)
known to host malware and/or be involved in the command and
control of bot nets, IP addresses know to host malware and/or be
involved in the command and control of bot nets, recently tested
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or discovered techniques or detecting or remediating bot
infections, new threat vectors, and other relevant information.
c. An ISP may use Netflow [RFC3954] or other similar passive network
monitoring to identify bots. For example, an ISP may be able to
identify compromised hosts by identifying traffic destined to IP
addresses associated with the command and control of bot nets.
d. An ISP may use DNS-based techniques to perform detection. For
example, a given classified bot may be known to query a specific
list of domain names at specific times or on specific dates (in
the example of the so-called "Konficker" bot network), typically
by matching DNS queries to a well known list of domains
associated with malware. In many cases such lists are
distributed by or shared using third parties, such as threat data
clearinghouses.
e. User complaints: Because botted hosts are frequently used to send
spam, the ISP servicing those botted hosts will normally receive
complaints about that spam. Those complaints may be sent to
RFC2142-specified [RFC2142] role accounts, such as abuse@ or
postmaster@ or to abuse or security addresses specified by the
site as part of its WHOIS (or other) contact data.
f. ISPs may also discover likely botted hosts located at other
sites; when legally permissible or otherwise an industry accepted
practice in a particular market region, it may be worthwhile for
ISPs to share evidence relating to those compromised hosts with
the relevant remote ISP, with security researchers, and with
blocklist operators.
5.2. Notification to Internet Users
Once an ISP has detected a bot, or the strong likelihood of a bot,
steps should be undertaken to inform the Internet user that they may
have a bot-related problem. Depending upon a range of factors, from
the technical capabilities of the ISP, to the technical attributes of
their network, financial considerations, available server resources,
available organizational resources, the number of likely infected
computers detected at any given time, and the severity of any
possible threats, among many other things, an ISP will decide the
most appropriate method or methods for providing notification to one
or more of their customers or Internet users. Such notification
methods may include one or more of the following, as well as other
possible methods not described below. It is important to note that
none of these methods are guaranteed to be successful, as each has
its own set of limitations. In addition, in some cases, and ISP may
determine that a combination of two or more methods is most
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appropriate. Finally, notification is also considered time
sensitive; if the user does not receive or view the notification or a
timely basis, then a particular bot could launch an attack, exploit
the user, or cause other harm.
5.2.1. Email Notification
This is probably the most common form of notification used by ISPs.
One drawback of using email is that it is not guaranteed to be viewed
within a reasonable time frame, if at all. The user may be using a
different primary email address than that which they have provided to
the ISP. In addition, some ISPs do not provide an email account at
all, as part of a bundle of Internet services, and/or do not have a
need for or manner in which to request or retain the primary email
addresses of Internet users of their networks. Another possibility
is that the user, their email client, and/or their email servers
could determine or classify such a notification as spam, which could
delete the message or otherwise file it in an email folder that the
user may not check on a regular and/or timely basis. Finally if the
user's email credentials are compromised, then a hacker and/or a bot
could simply login to the user's email account and delete the email
before it is read by the user.
5.2.2. Telephone Call Notification
A telephone call may be an effective means of communication in
particularly high-risk situations. However, telephone calls may not
be feasible due to the cost of making a large number of times, as
measured in either time, money, organizational resources, server
resources, or some other means. In addition, there is no guarantee
that the user will answer their phone. To the extent that the
telephone number called by the ISP can be answered by the infected
computing device, the bot on that computer may be able to disconnect,
divert, or otherwise interfere with an incoming call. Users may also
interpret such a telephone notification as a telemarketing call and
as such not welcome it, or not accept the call at all. Finally, even
if a representative of the ISP is able to connect with and speak with
a user, that user is very likely to lack the necessary technical
experience to understand or be able to effectively deal with the
threat.
5.2.3. Postal Mail Notification
This form of notification is probably the least popular means of
communication, due to both preparation time, delivery time and cost.
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5.2.4. Walled Garden Notification
Placing a user in a so-called walled garden is another approach that
ISPs may take to notify users. This is an effective technique
because it could be able to block all communication between the bot
and the command and control channel, which may impair the ability of
a bot to disrupt or block attempts to notify the user.
While in many cases, the user is almost guaranteed to view the
notification message and take any appropriate remediation actions,
this approach poses can pose other challenges. For example, it is
not always the case that a user is actively using a computer that
uses a web browser or which has a web browser actively running on it.
In one case, a user could be playing a game online, via the use of a
dedicated, Internet-connected game console. In another case, the
user may not be using a computer with a web browser when they are
placed in the walled garden and may instead be in the course of a
telephone conversation, or may be expecting to receive a call, using
a Voice Over IP (VOIP) device of some type. As a result, the ISP may
feel the need to maintain a potentially lengthy white list of domains
which are not subject to the typical restrictions of a walled garden,
which could well prove to be an onerous task, from an operational
perspective.
The ISP has several options to determine when to let the user out of
the walled garden. One approach may be to let the user determine
when to exit. This option is suggested when the purpose of the
walled garden is to notify users and provide information on
remediation only, particularly since notification is not a guarantee
of successful remediation. It could also be the case that, for
whatever reason, the user makes the judgement that they cannot then
take the time to remediate their computer and that other online
activities which they would like to resume are more important.
Once the user acknowledges the notification, then the user decides to
either remediate and then exit the walled garden, or exit the walled
garden without addressing the issue. Another approach may be to
enforce a stricter policy and require the user to clean the computer
prior to permitting the user to exit the walled garden, though this
may not be technically feasible depending upon the type of bot,
obfuscation techniques employed by a bot, and/or a range of other
factors. Thus, the ISP may also need to support tools to scan the
infected computer and determine whether it is still infected or rely
on user judgement that the bot has been disabled or removed. One
challenge with this approach is that if the user has multiple
computers sharing a single IP address, such as via a common home
gateway device which performs Network Address Translation (NAT), then
the ISP may need to determine from user feedback or other means that
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all affected computers have been remediated, which may or may not be
technically feasible.
5.2.5. Instant Message Notification
Instant Message (IM): Instant messaging provides the ISP with a
simple means to communicate with the user. There are several
advantages of using IM which makes it an attractive option. First,
if the ISP provides IM service and the user subscribes to it then the
user can be notified easily. Second, IM based notification can be
cost effective means to communicate with the use. This can be
achieved by signing up for IM service with the various popular IM
providers and programatically messaging, if permitted by the
acceptable usage policy, the notifications. However, it IM based
notification can also be done manually by the ISP's support staff.
Ideally, the ISP should allow the user to register the IM identity
and seek permission to be contacted via this mean. Third, if the IM
service provider supports offline messaging the user can be notified
regardless of their signed in status. Essentially a message can be
sent and when the user signs in they would receive it. There are
several drawbacks with this communications method. First, there is a
high probability that subscriber may interpret the communication to
be spam and as such ignore it. Second, not every user uses IM and/or
the user may not provide their IM identity to the ISP so some
alternative means have to be used. Third, there maybe a privacy
concern when the communication between the ISP and the end user is
not secure and over a third party network and/or IM service. As such
the notification must be discreet and not provide any personally
identifiable information.
5.2.6. Short Message Service (SMS) Notification
Short Message Service (SMS): SMS allows the ISP send a brief
description of the problem to notify the user of the issue. ISP
should allow users to register their mobile number for notifications
and also allow users to opt out if they do not wish to be notified.
The primary advantage of SMS is that users are used to receiving text
messages and are likely to read them. Although users may not act on
it immediately if they are not in front of their computer system.
One disadvantage is that ISPs may have to follow up with an alternate
means of communication if since a SMS message is restricted to 166
characters and not all of the necessary information maybe conveyed in
one message. Another disadvantage is the cost associated with SMS.
The ISP has to either build its own SMS gateway to interface with the
various wireless providers or use a third party provider to notify
users. It is recommended that the ISP absorb the cost of
notification and should always state in the notification that the
message is free of charge to the user. Another small disadvantage is
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that it is possible to notify the wrong user if the intended user
changes their mobile number but forgets to update it with the ISP.
5.2.7. Web Browser Notification
Near real-time notification to the user's web browser is another
technique that may be utilized for notifying the user, though how
such a system might operate is outside the scope of this document.
Such a notification could have a comparative advantage over a walled
garden notification, in that it does not restrict traffic to a
specified list of destinations in the same way that a walled garden
by definition would. However, as with a walled garden notification,
there is no guarantee that a user is at any given time making use of
a web browser, though such a system could certainly provide a
notification when such a browser is eventually used. Compared to a
walled garden, a web browser notification is probably preferred from
the perspective of Internet users, as it does not have the risk of
disrupting non-web sessions, such as online games, etc. (as noted in
Section 5.2.4).
5.3. Remediation of Bot Infected Machines
This section covers the different options available to remediate a
computer, which means to remove, disable, or otherwise render a bot
harmless. Prior to this step, an ISP has detected the bot, notified
the user that one of their computers is infected with a bot, and now
has to provide some means to clean the PC. The generally recommended
approach is to provide the necessary tools and education to the user
so that they may perform bot remediation themselves.
For example, this may include the creation of a special Security Web
Portal. This should be a well-publicized security portal to which a
user with a bot problem can be directed to for remediation. This
Security Web Portal should clearly explain why the user was notified
and may include an explanation of what bots are and the threats that
they pose. There should be a clear explanation of the steps that the
user should take in order to clean the computers and provide
information on how users can keep the computer free of future
infections. The Security Web Portal should have a guided process
that takes non technical users through the remediation process.
In terms of the text user to explain what bots are and the threat
they pose, something simple such as this may suffice:
"What is a bot? A bot is a piece of software, generally installed on
your machine without your knowledge, which either sends spam or tries
to steal your personal information. They can be very difficult to
spot, though you may have noticed that your computer is running much
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more slowly than usual or you notice regular disk activity even when
you are not doing anything. Ignoring this problem is not really an
option since your personal information is currently at risk. Thus,
bots need to be removed to protect your data and your personal
information."
5.4. Guided Remediation Process
Minimally the Guided Remediation Process should include options
and/or recommendations on how a user should:
1. If the user is interested in reporting his or her computer's bot
infection to an applicable law enforcement authority, then the
computer effectively becomes a cyber "crime scene" and should not
be mitigated unless or until law enforcement has collected the
necessary evidence. For individuals in this situation, the ISP
should refer them to local, state, federal, or other relevant
computer crime offices. (Note: Some "minor" incidents, even if
highly traumatic to the user, may not be sufficiently serious for
law enforcement to commit some of their limited resources to an
investigation.)
2. Regardless of whether the user or a knowledgeable technical
assistant is working on remediating the computer, their first
task should be to determine which of multiple potentially-
infected machines may be the one that needs attention (in the
common case of multiple computers in a home network). Sometimes,
as in cases where there is only a single directly-attached
computer, or the user has been noticing problems with one of
their computers, this can be easy. Other times, it may be more
difficult. If the user is behind a home gateway/router, then the
first task may be to ascertain which of the machines is infected.
In some cases the user may have to check all machines to identify
the infected one. Thus, it is possible that an individual
computer may have multiple bot infections and, in addition,
multiple computers on the home network may be infected.
3. Perform a FULL backup of the affected computers.
4. Download OS patches and Anti-Virus (A/V) software updates. For
example, for OS patches, links could be provided to Microsoft
Windows updates and Apple MacOS updates could be provided.
5. Run a scan using installed A/V software.
6. Explain how to configure the computer to automatically install
updates for the OS, A/V and other common Web Browsers such as
Microsoft Internet Explorer, Mozilla Firefox, Apple Safari,
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Opera, and Google Chrome.
7. The flow should also have the option for users to get
professional assistance if they are unable to remove the bots
themselves. If purchasing third party assistance, then the user
should be encouraged to pre-determine how much they are willing
to pay for that help. If the computer that is being remediated
is old and can easily be replaced with a new, faster, larger and
more reliable system for three or four hundred dollars, the it
makes no sense to spend five or six hundred dollars to fix the
old computer, for example. On the other hand, if the customer
has a brand new computer that cost several thousand dollars, it
might make perfect sense to spend the money in attempting to
remediate it.
8. User surveys to solicit feedback on whether the notification and
remediation process is effective and what recommended changes
could be made in order to improve the ease, understandability,
and effectiveness the remediation process.
There are many cases where a user may not be a residential user, in
which case some of these steps may not apply. For example, the user
may be part of a business, educational institution, non-profit
company, or other organization. In these cases, the user should
immediately seek out the support of their information technology
support team.
6. Security Considerations
Scanning systems for missing patches, while a good and necessary
task, may nonetheless result in systems being knocked offline.
Conveying a system to a third party for cleaning may result in
sensitive contents of that system (confidential email or images,
unauthorized access to remote systems via stored passwords, etc.)
being inadvertently disclosed to the third party.
Passive network monitoring, even of encrypted traffic, may result in
sensitive information leaking (e.g., merely knowing that a user is
connecting to a site about a particular subject may prompt one to
infer an interest in that particular subject).
7. IANA Considerations
There are no IANA considerations in this document.
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8. Contributors
The authors wish to acknowledge the following individuals for their
textual contribution to and detailed reviews of this document:
Joe St. Sauver, University of Oregon and Internet2 (joe@uoregon.edu)
9. Normative References
[RFC1459] Oikarinen, J. and D. Reed, "Internet Relay Chat Protocol",
RFC 1459, May 1993.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2142] Crocker, D., "MAILBOX NAMES FOR COMMON SERVICES, ROLES AND
FUNCTIONS", RFC 2142, May 1997.
[RFC3954] Claise, B., "Cisco Systems NetFlow Services Export Version
9", RFC 3954, October 2004.
Appendix A. Document Change Log
[RFC Editor: This section is to be removed before publication]
-00 version:
o -00 version published
Appendix B. Open Issues
[RFC Editor: This section is to be removed before publication]
Could use some informational references in Section 3
Fix the odd list spacing in Section 5.1
Add some point about notification to large networks may not be useful
-- such as coffee shops or hotels with WiFi networks.
Consider combining 5.b and 5.f., and possibly re-wording some of the
other items.
Consider adding mention to the use of ccleaner in section 5.4
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Significantly revise and expand section 5.4
Add discussion of root kits and other bits of malware that may
actively resist detection and removal (e.g., attempting to disinfect
a system while running an infected OS can be a rather futile
exercise; you have a much better chance of detecting malware if you
mount the infected disk on a third party system for review and
disinfection)
add discussion on restoring files from the backups if nuke and pave
is required.
add discussion of user education to help prevent repeat infections
consider adding discussion of the ISP's role in the remediation
process -- I think this is a key consideration. Liability issues,
cost issues and other factors should be laid out so that users
understand why the ISP doesn't just "do it for them."
Authors' Addresses
Jason Livingood
Comcast Cable Communications
One Comcast Center
1701 John F. Kennedy Boulevard
Philadelphia, PA 19103
US
Email: jason_livingood@cable.comcast.com
URI: http://www.comcast.com
Nirmal Mody
Comcast Cable Communications
One Comcast Center
1701 John F. Kennedy Boulevard
Philadelphia, PA 19103
US
Email: nirmal_mody@cable.comcast.com
URI: http://www.comcast.com
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Mike O'Reirdan
Comcast Cable Communications
One Comcast Center
1701 John F. Kennedy Boulevard
Philadelphia, PA 19103
US
Email: michael_oreirdan@cable.comcast.com
URI: http://www.comcast.com
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