Linux-PAM up to 1.1.4 _expand_arg memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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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), Tenable (57002), SecurityFocus (BID 50343†) and Vulnerability Center (SBV-33655†). The entries VDB-61381 and VDB-69363 are pretty similar.

Productinfo

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Version

CPE 2.3info

CPE 2.2info

CVSSv4info

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CVSSv3info

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

VulDB Base Score: 4.0
VulDB Temp Score: 3.8
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CVSSv2info

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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

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EPSS Percentile: 🔍

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Current Price Estimation: 🔍

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

See also: 🔍

Entryinfo

Created: 03/23/2015 04:50 PM
Updated: 12/06/2021 07:13 PM
Changes: 03/23/2015 04:50 PM (64), 04/04/2017 11:30 AM (9), 12/06/2021 07:05 PM (7), 12/06/2021 07:13 PM (1)
Complete: 🔍
Cache ID: 18:4B4:40

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