Exim < 4.76 dkim_exim_verify_finish() DKIM-Signature Header Format String

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


Synopsis :

The remote mail server is potentially affected by a format string
vulnerability.

Description :

Based on its response to a specially formatted mail message, the Exim
mail server listening on this port appears to be affected by a format
string vulnerability.

Specifically, the 'dkim_exim_verify_finish()' function fails to
properly sanitize format string specifiers in the DKIM-Signature
header. By sending a specially crafted email, a remote attacker could
potentially execute arbitrary code as the Exim run-time user.

See also :

ftp://ftp.exim.org/pub/exim/ChangeLogs/ChangeLog-4.76
http://www.nessus.org/u?f4efd3a2
http://bugs.exim.org/show_bug.cgi?id=1106

Solution :

Upgrade to Exim 4.76 or later.

Risk factor :

High / CVSS Base Score : 7.5
(CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P)
CVSS Temporal Score : 6.5
(CVSS2#E:ND/RL:OF/RC:C)
Public Exploit Available : false

Family: SMTP problems

Nessus Plugin ID: 53856 ()

Bugtraq ID: 47736
47836

CVE ID: CVE-2011-1407
CVE-2011-1764