Mail Transfer Agent and Mail Delivery Agent Remote Command Execution via Shellshock

critical Nessus Plugin ID 78701
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Synopsis

The remote host has a mail agent installed that allows remote command execution via Shellshock.

Description

The remote host appears to be running a mail transfer or mail delivery agent such as Courier, Exim, Postfix, or Procmail. Many of these agents can be configured to run utility scripts for a diverse number of tasks including filtering, sorting, and delivering mail. These scripts may create the conditions that are exploitable, making the agent vulnerable to remote code execution via Shellshock.

A negative result from this plugin does not prove conclusively that the remote system is not affected by Shellshock, only that the mail agent running on the system is not configured in such a way to allow remote execution via Shellshock.

Solution

Apply the referenced Bash patch.

See Also

http://seclists.org/oss-sec/2014/q3/650

http://www.nessus.org/u?dacf7829

https://www.invisiblethreat.ca/post/shellshock/

Plugin Details

Severity: Critical

ID: 78701

File Name: shellshock_mail_agents.nasl

Version: 1.10

Type: remote

Published: 10/28/2014

Updated: 7/27/2018

Dependencies: smtpserver_detect.nasl

Risk Information

VPR

Risk Factor: Critical

Score: 9.8

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 8.7

Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: E:H/RL:OF/RC:C

Vulnerability Information

CPE: cpe:/a:gnu:bash

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 10/24/2014

Vulnerability Publication Date: 9/24/2014

Exploitable With

Core Impact

Metasploit (Apache mod_cgi Bash Environment Variable Code Injection (Shellshock))

Reference Information

CVE: CVE-2014-6271, CVE-2014-7169

BID: 70103, 70137

CERT: 252743

IAVA: 2014-A-0142

EDB-ID: 34765, 34766, 34777, 34896