GNU C Library up to 2.19.18+deb8u3 on Debian Linux debian/sysdeps/ pt_chown access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability classified as critical has been found in GNU C Library up to 2.19.18+deb8u3 on Debian Linux (Software Library). Affected is the function pt_chown of the file debian/sysdeps/ The manipulation with an unknown input leads to a access control vulnerability. CWE is classifying the issue as CWE-264. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was published 03/14/2016 (oss-sec). The advisory is shared for download at This vulnerability is traded as CVE-2016-2856 since 03/06/2016. The attack needs to be approached locally. Required for exploitation is a authentication. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1068.

The vulnerability scanner Nessus provides a plugin with the ID 91334 (Ubuntu 12.04 LTS / 14.04 LTS / 15.10 : eglibc, glibc vulnerabilities (USN-2985-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Ubuntu Local Security Checks and running in the context local. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196484 (Ubuntu Security Notification for Eglibc, Glibc Vulnerabilities (USN-2985-1)).

Upgrading to version 2.19-18+deb8u4 eliminates this vulnerability. A possible mitigation has been published 3 months after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Vulnerability Center (SBV-57689) and Tenable (91334). Similar entries are available at 10583, 73929, 75092 and 79344.






  • open-source

CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 8.4
VulDB Meta Temp Score: 8.2

VulDB Base Score: 8.4
VulDB Temp Score: 8.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.4
NVD Vector: 🔍



VulDB Base Score: 🔍
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Class: Access control
CWE: CWE-264
ATT&CK: T1068

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Nessus ID: 91334
Nessus Name: Ubuntu 12.04 LTS / 14.04 LTS / 15.10 : eglibc, glibc vulnerabilities (USN-2985-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 841810
OpenVAS Name: Ubuntu Update for glibc USN-2985-2
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Active APT Groups: 🔍


Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
Exposure Time: 🔍

Upgrade: C Library 2.19-18+deb8u4


02/23/2016 🔍
03/06/2016 +12 days 🔍
03/13/2016 +7 days 🔍
03/13/2016 +0 days 🔍
03/14/2016 +1 days 🔍
03/14/2016 +0 days 🔍
03/24/2016 +10 days 🔍
05/25/2016 +62 days 🔍
05/26/2016 +1 days 🔍
07/10/2022 +2236 days 🔍



Advisory: USN-2985-1
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-2856 (🔍)
Vulnerability Center: 57689 - Gnu glibc before 2.19-18+deb8u4 Local Data Spoofing and Privilege Escalation Vulnerability, Medium
SecurityFocus: 84601 - GNU glibc 'pt_chown' Local Security Bypass Vulnerability

See also: 🔍


Created: 03/14/2016 09:24 AM
Updated: 07/10/2022 11:25 AM
Changes: 03/14/2016 09:24 AM (75), 02/02/2019 11:36 AM (13), 07/10/2022 11:25 AM (4)
Complete: 🔍


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