Vulnerability Assessment & Network Security Forums



If through a vulnerability assessment, a network security issue is detected for the vulnerability below, applying the appropriate security patches in a timely matter is very important.  If you have detected that your system has already been compromised, following CERT's Network Security recovery document will assist with recommended steps for system recovery.


Home >> Browse Vulnerability Assessment Database >> Gentoo Local Security Checks >> [GLSA-200407-12] Linux Kernel: Remote DoS vulnerability with IPTables TCP Handling


Vulnerability Assessment Details

[GLSA-200407-12] Linux Kernel: Remote DoS vulnerability with IPTables TCP Handling

Vulnerability Assessment Summary
Linux Kernel: Remote DoS vulnerability with IPTables TCP Handling

Detailed Explanation for this Vulnerability Assessment
The remote host is affected by the vulnerability described in GLSA-200407-12
(Linux Kernel: Remote DoS vulnerability with IPTables TCP Handling)


A possible hacker can utilize an erroneous data type in the IPTables TCP option
handling code, which lies in an iterator. By making a TCP packet with a
header length larger than 127 bytes, a negative integer would be implied in
the iterator.

Impact

By sending one malformed packet, the kernel could get stuck in a loop,
consuming all of the CPU resources and rendering the machine useless,
causing a Denial of Service. This vulnerability requires no local access.

Workaround

If users do not use the netfilter functionality or do not use any
``--tcp-option'' rules they are not vulnerable to this exploit. Users that
are may remove netfilter support from their kernel or may remove any
``--tcp-option'' rules they might be using. However, all users are urged to
upgrade their kernels to patched versions.

References:
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2004-0626


Solution:
Users are encouraged to upgrade to the latest available sources for their
system:
# emerge sync
# emerge -pv your-favorite-sources
# emerge your-favorite-sources
# # Follow usual procedure for compiling and installing a kernel.
# # If you use genkernel, run genkernel as you would do normally.


Network Security Threat Level: High


Networks Security ID:

Vulnerability Assessment Copyright: (C) 2005 Michel Arboi

Cables, Connectors

Dell R720xd 8-Core Server 2x E5-2609 v2 2.5GHz 32GB 12x 8TB, 2x 480GB 3.5in
$5579.0
Dell R720xd 8-Core Server 2x E5-2609 v2 2.5GHz 32GB 12x 8TB, 2x 480GB 3.5in pictureDell R630 16-Core Server 2x E5-2630 v3 2.4GHz 16GB H730 8x 1TB SAS
$3088.0
Dell R630 16-Core Server 2x E5-2630 v3 2.4GHz 16GB H730 8x 1TB SAS pictureDell R720xd 24-Core Server 2x E5-2697 v2 2.7GHz 64GB 12x 6TB, 2x 480GB 3.5in
$5522.0
Dell R720xd 24-Core Server 2x E5-2697 v2 2.7GHz 64GB 12x 6TB, 2x 480GB 3.5in pictureDell R730xd 16-Core Server 2x E5-2640 v3 2.6GHz 768GB 16x 600GB 2.5in H730 Rails
$12637.0
Dell R730xd 16-Core Server 2x E5-2640 v3 2.6GHz 768GB 16x 600GB 2.5in H730 Rails picture


Discussions

No Discussions have been posted on this vulnerability.