Linux-PAM up to 1.1.4 _expand_arg memory corruption

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
3.8$0-$5k0.00

A vulnerability, which was classified as problematic, has been found in Linux-PAM. Affected by this issue is the function _expand_arg. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is availability. CVE summarizes:

The _expand_arg function in the pam_env module (modules/pam_env/pam_env.c) in Linux-PAM (aka pam) before 1.1.5 does not properly handle when environment variable expansion can overflow, which allows local users to cause a denial of service (CPU consumption).

The weakness was disclosed 07/22/2012 as confirmed git commit (GIT Repository). The advisory is available at git.fedorahosted.org. This vulnerability is handled as CVE-2011-3149. The exploitation is known to be easy. Local access is required to approach this attack. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 57002 (Fedora 16 : pam-1.1.5-1.fc16 (2011-16390)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 350586 (Amazon Linux Security Advisory for pam: ALAS-2013-160).

Upgrading to version 0.99.7.0 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.fedorahosted.org. The best possible mitigation is suggested to be patching the affected component.

The vulnerability is also documented in the databases at X-Force (70936) and Tenable (57002). The entries 61381 and 69363 are pretty similar.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.0
VulDB Meta Temp Score: 3.8

VulDB Base Score: 4.0
VulDB Temp Score: 3.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
ATT&CK: Unknown

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Dayunlockunlockunlockunlock
Todayunlockunlockunlockunlock

Nessus ID: 57002
Nessus Name: Fedora 16 : pam-1.1.5-1.fc16 (2011-16390)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Port: 🔍

OpenVAS ID: 70541
OpenVAS Name: Debian Security Advisory DSA 2326-1 (pam)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Upgrade: Linux-PAM 0.99.7.0
Patch: 109823cb621c900c07c4b6cdc99070d354d19444

Timelineinfo

08/16/2011 🔍
10/14/2011 +59 days 🔍
10/24/2011 +10 days 🔍
10/31/2011 +7 days 🔍
12/05/2011 +35 days 🔍
07/22/2012 +230 days 🔍
07/22/2012 +0 days 🔍
03/23/2015 +974 days 🔍
12/06/2021 +2450 days 🔍

Sourcesinfo

Advisory: USN-1237-1
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2011-3149 (🔍)
OVAL: 🔍

X-Force: 70936
Vulnerability Center: 33655 - Linux-PAM 1.1.2 _expand_arg() Infinite Loop Error Allows Local Denial of Service, Low
SecurityFocus: 50343 - Linux-PAM 'pam_env' Module Multiple Local Privilege Escalation Vulnerabilities
Secunia: 46583

See also: 🔍

Entryinfo

Created: 03/23/2015 16:50
Updated: 12/06/2021 19:13
Changes: 03/23/2015 16:50 (64), 04/04/2017 11:30 (9), 12/06/2021 19:05 (7), 12/06/2021 19:13 (1)
Complete: 🔍

Discussion

No comments yet. Languages: en.

Please log in to comment.

Want to stay up to date on a daily basis?

Enable the mail alert feature now!