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

Medium Nessus Plugin ID 57287


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


According to its banner, the version of Squid is 3.1.x earlier than than 3.1.16 or 3.2.x earlier than 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.


Upgrade to Squid version 3.1.16 / or later.

See Also




Plugin Details

Severity: Medium

ID: 57287

File Name: squid_3_1_16.nasl

Version: $Revision: 1.6 $

Type: remote

Family: Firewalls

Published: 2011/12/14

Modified: 2014/05/26

Dependencies: 49692

Risk Information

Risk Factor: Medium


Base Score: 5

Temporal Score: 4.3

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

Temporal Vector: CVSS2#E:ND/RL:OF/RC:C

Vulnerability Information

CPE: cpe:/a:squid-cache:squid

Required KB Items: www/squid, Settings/ParanoidReport

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 2011/10/08

Vulnerability Publication Date: 2011/10/08

Reference Information

CVE: CVE-2011-4096

BID: 50449

OSVDB: 76742