Squid 3.1.x < 3.1.16 / 3.2.x < 3.2.0.13 DNS Replies CName Record Parsing Remote DoS

This script is Copyright (C) 2011-2014 Tenable Network Security, Inc.


Synopsis :

The remote proxy server is affected by a denial of service
vulnerability.

Description :

According to its banner, the version of Squid is 3.1.x earlier than
than 3.1.16 or 3.2.x earlier than 3.2.0.13. Such versions are affected
by a denial of service vulnerability.

The application does not properly free memory when handling DNS
replies containing a CNAME record that references another CNAME record
that contains an empty A record.

Note that Nessus has relied only on the version in the proxy server's
banner, which is not updated by the patch that the project has
released to address the issue. If the patch has been applied properly
and the service restarted, consider this to be a false positive.

See also :

http://www.squid-cache.org/Versions/v3/3.1/changesets/SQUID_3_1_16.html
http://www.nessus.org/u?437bac7c
http://bugs.squid-cache.org/show_bug.cgi?id=3237

Solution :

Upgrade to Squid version 3.1.16 / 3.2.0.13 or later.

Risk factor :

Medium / CVSS Base Score : 5.0
(CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P)
CVSS Temporal Score : 4.3
(CVSS2#E:ND/RL:OF/RC:C)
Public Exploit Available : true

Family: Firewalls

Nessus Plugin ID: 57287 ()

Bugtraq ID: 50449

CVE ID: CVE-2011-4096