Linux Kernel up to 4.4.0 Mutex sound/core/timer.c IOCTL Call race condition

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability has been found in Linux Kernel up to 4.4.0 (Operating System) and classified as critical. Affected by this vulnerability is an unknown function of the file sound/core/timer.c of the component Mutex. The manipulation as part of a IOCTL Call leads to a race condition vulnerability. The CWE definition for the vulnerability is CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

sound/core/timer.c in the Linux kernel before 4.4.1 uses an incorrect type of mutex, which allows local users to cause a denial of service (race condition, use-after-free, and system crash) via a crafted ioctl call.

The weakness was disclosed 04/27/2016 (Website). The advisory is shared at This vulnerability is known as CVE-2016-2546 since 02/22/2016. An attack has to be approached locally. The successful exploitation requires a single authentication. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 89122 (Debian DSA-3503-1 : linux - security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196465 (Ubuntu Security Notification for Linux Vulnerabilities (USN-2967-1)).

Upgrading to version 4.4.1 eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (89122).







CPE 2.3info

CPE 2.2info


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VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

VulDB Base Score: 9.8
VulDB Temp Score: 9.4
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NVD Base Score: 5.1
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Class: Race condition
CWE: CWE-362

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

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Nessus ID: 89122
Nessus Name: Debian DSA-3503-1 : linux - security update
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OpenVAS ID: 703503
OpenVAS Name: Debian Security Advisory DSA 3503-1 (linux - security update)
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Recommended: Upgrade
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Upgrade: Kernel 4.4.1


02/22/2016 🔍
02/22/2016 +0 days 🔍
03/02/2016 +9 days 🔍
03/03/2016 +1 days 🔍
04/27/2016 +54 days 🔍
04/27/2016 +0 days 🔍
04/28/2016 +1 days 🔍
07/27/2022 +2281 days 🔍



Advisory: USN-2929-1
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-2546 (🔍)

SecurityTracker: 1035301
SecurityFocus: 83384 - Linux Kernel CVE-2016-2546 Use After Free Denial of Service Vulnerability


Created: 04/28/2016 10:24 AM
Updated: 07/27/2022 08:09 AM
Changes: 04/28/2016 10:24 AM (67), 10/29/2018 05:53 AM (15), 07/27/2022 08:09 AM (6)
Complete: 🔍
Cache ID: 44:B5E:40


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