Date: Tue, 20 Nov 2001 14:18:40 -0500 (EST)
From: CERT Advisory <[email protected]>
To: [email protected]Subject: CERT Summary CS-2001-04
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CERT Summary CS-2001-04
November 20, 2001
Each quarter, the CERT Coordination Center (CERT/CC) issues the CERT
Summary to draw attention to the types of attacks reported to our
incident response team, as well as other noteworthy incident and
vulnerability information. The summary includes pointers to sources of
information for dealing with the problems.
Past CERT summaries are available from:
CERT Summaries
http://www.cert.org/summaries/
______________________________________________________________________
Recent Activity
Since the last regularly scheduled CERT summary, issued in August 2001
(CS-2001-03), we have seen a new worm known as "Nimda," as well as
active exploitation of a vulnerability in Microsft DNS servers. In
addition, we have published a paper on denial of service trends,
issued a new PGP key, and updated the UNIX Security Checklist.
For more current information on activity being reported to the
CERT/CC, please visit the CERT/CC Current Activity page. The Current
Activity page is a regularly updated summary of the most frequent,
high-impact types of security incidents and vulnerabilities being
reported to the CERT/CC. The information on the Current Activity page
is reviewed and updated as reporting trends change.
CERT/CC Current Activity
http://www.cert.org/current/current_activity.html
1. W32/Nimda Worm
Over the past several months, we have received reports of
malicious code known as the "W32/Nimda Worm." This worm can
propogate itself via several methods, including email, network
shares, or by visiting an infected web site. On September 18, the
CERT/CC issued an advisory on Nimda.
CERT Advisory CA-2001-26: Nimda Worm
http://www.cert.org/advisories/CA-2001-26.html
2. Exploitation of Vulnerability in
SSH1 CRC-32 Compensation Attack Detector
The CERT/CC has received multiple reports of systems being
compromised via the CRC-32 compensation attack detector
vulnerability (VU#945216). On November 5, the CERT/CC released an
incident note which describes system compromises via a
vulnerability in the SSH1 (Secure Shell Protocol v1) CRC-32 attack
detection code. Consequentially, we are also receiving reports of
increased scanning activity for the SSH service (22/tcp).
Incident Note IN 2001-12: Exploitation of vulnerability
in SSH1 CRC-32 compensation attack detector
http://www.cert.org/incident_notes/IN-2001-12.html
Vulnerability Note #945216: SSH CRC32 attack detection
code contains remote integer overflow
http://www.kb.cert.org/vuls/id/945216
3. DNS Cache Poisoning in Microsoft DNS Servers
The CERT/CC has received reports from sites experiencing cache
corruption on systems running Microsoft DNS Server. We issued an
incident note which describes this corruption and its impact on
systems. The default configuration of this software allows data
from malicious or incorrectly configured DNS servers to be cached
by a Microsoft DNS server. This corruption can result in erroneous
DNS information being returned to clients which use this server.
Incident Note IN-2001-11: Cache Corruption on Microsoft
DNS Servers
http://www.cert.org/incident_notes/IN-2001-11.html
Vulnerability Note #109475: Microsoft Windows NT and 2000
Domain Name Servers allow non-authoritative RRs to be
cached by default
http://www.kb.cert.org/vuls/id/109475
4. Trends In Denial Of Service Attack Technology
This paper describes the current and possible future states of
denial of service (DoS) technology. This document is in Adobe
Acrobat format, and requires Acrobat Reader.
Trends In Denial Of Service Attack Technology
http://www.cert.org/archive/pdf/DoS_trends.pdf
______________________________________________________________________
UNIX Security Checklist Version 2.0
The CERT Coordination Center and the Australian Computer Emergency
Response Team (AusCERT) have jointly published version 2.0 of the UNIX
Security Checklist which details steps to improve the security of UNIX
Operating Systems. We encourage system administrators to review all
sections of this document and, if appropriate, modify their systems
accordingly to fix potential weaknesses.
AUSCERT UNIX Security Checklist
http://www.cert.org/tech_tips/AUSCERT_checklist2.0.html
______________________________________________________________________
New CERT/CC PGP Key
On October 1, the CERT/CC issued a new PGP key, which should be used
when sending sensitive information to the CERT/CC.
CERT/CC PGP Public Key
https://www.cert.org/pgp/cert_pgp_key.asc
Sending Sensitive Information To The CERT/CC
http://www.cert.org/contact_cert/encryptmail.html
______________________________________________________________________
What's New and Updated
Since the last CERT Summary, we have published new and updated
* Advisories
http://www.cert.org/advisories/
* Congressional Testimony
http://www.cert.org/congressional_testimony/
* Incident Notes
http://www.cert.org/incident_notes/
* CERT/CC Statistics
http://www.cert.org/stats/cert_stats.html
* Tech Tips
http://www.cert.org/tech_tips/
* Training Schedule
http:/www.cert.org/training/
* UNIX Security Checklist v2.0
http://www.cert.org/tech_tips/unix_security_checklist2.0.html
______________________________________________________________________
This document is available from:
http://www.cert.org/summaries/CS-2001-04.html
______________________________________________________________________
CERT/CC Contact Information
Email: [email protected]
Phone: +1 412-268-7090 (24-hour hotline)
Fax: +1 412-268-6989
Postal address:
CERT Coordination Center
Software Engineering Institute
Carnegie Mellon University
Pittsburgh PA 15213-3890
U.S.A.
CERT/CC personnel answer the hotline 08:00-17:00 EST(GMT-5) /
EDT(GMT-4) Monday through Friday; they are on call for emergencies
during other hours, on U.S. holidays, and on weekends.
Using encryption
We strongly urge you to encrypt sensitive information sent by email.
Our public PGP key is available from
http://www.cert.org/CERT_PGP.key
If you prefer to use DES, please call the CERT hotline for more
information.
Getting security information
CERT publications and other security information are available from
our web site
http://www.cert.org/
To subscribe to the CERT mailing list for advisories and bulletins,
send email to [email protected]. Please include in the body of your
message
subscribe cert-advisory
* "CERT" and "CERT Coordination Center" are registered in the U.S.
Patent and Trademark Office.
______________________________________________________________________
NO WARRANTY
Any material furnished by Carnegie Mellon University and the Software
Engineering Institute is furnished on an "as is" basis. Carnegie
Mellon University makes no warranties of any kind, either expressed or
implied as to any matter including, but not limited to, warranty of
fitness for a particular purpose or merchantability, exclusivity or
results obtained from use of the material. Carnegie Mellon University
does not make any warranty of any kind with respect to freedom from
patent, trademark, or copyright infringement.
_________________________________________________________________
Conditions for use, disclaimers, and sponsorship information
Copyright ╘2001 Carnegie Mellon University.
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