CVE-2021-47494

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2021-47494
In the Linux kernel, the following vulnerability has been resolved: cfg80211: fix management registrations locking The management registrations locking was broken, the list was locked for each wdev, but cfg80211_mgmt_registrations_update() iterated it without holding all the correct spinlocks, causing list corruption. Rather than trying to fix it with fine-grained locking, just move the lock to the wiphy/rdev (still need the list on each wdev), we already need to hold the wdev lock to change it, so there's no contention on the lock in any case. This trivially fixes the bug since we hold one wdev's lock already, and now will hold the lock that protects all lists.

5.5 /10

CVSS v3 : MEDIUM

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://git.kernel.org/stable/c/09b1d5dc6ce1c9151777f6c4e128a59457704c97 Patch
https://git.kernel.org/stable/c/3c897f39b71fe68f90599f6a45b5f7bf5618420e Patch
https://git.kernel.org/stable/c/4c22227e39c7a0b4dab55617ee8d34d171fab8d4 Patch
https://git.kernel.org/stable/c/09b1d5dc6ce1c9151777f6c4e128a59457704c97 Patch
https://git.kernel.org/stable/c/3c897f39b71fe68f90599f6a45b5f7bf5618420e Patch
https://git.kernel.org/stable/c/4c22227e39c7a0b4dab55617ee8d34d171fab8d4 Patch
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc7:*:*:*:*:*:*
History

24 Sep 2025, 19:14

Type Values Removed Values Added
CPE cpe:2.3:o:linux:linux_kernel:5.15:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc7:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*
First Time Linux
Linux linux Kernel
CWE CWE-667
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.5
References () https://git.kernel.org/stable/c/09b1d5dc6ce1c9151777f6c4e128a59457704c97 - () https://git.kernel.org/stable/c/09b1d5dc6ce1c9151777f6c4e128a59457704c97 - Patch
References () https://git.kernel.org/stable/c/3c897f39b71fe68f90599f6a45b5f7bf5618420e - () https://git.kernel.org/stable/c/3c897f39b71fe68f90599f6a45b5f7bf5618420e - Patch
References () https://git.kernel.org/stable/c/4c22227e39c7a0b4dab55617ee8d34d171fab8d4 - () https://git.kernel.org/stable/c/4c22227e39c7a0b4dab55617ee8d34d171fab8d4 - Patch

21 Nov 2024, 06:36

Type Values Removed Values Added
References () https://git.kernel.org/stable/c/09b1d5dc6ce1c9151777f6c4e128a59457704c97 - () https://git.kernel.org/stable/c/09b1d5dc6ce1c9151777f6c4e128a59457704c97 -
References () https://git.kernel.org/stable/c/3c897f39b71fe68f90599f6a45b5f7bf5618420e - () https://git.kernel.org/stable/c/3c897f39b71fe68f90599f6a45b5f7bf5618420e -
References () https://git.kernel.org/stable/c/4c22227e39c7a0b4dab55617ee8d34d171fab8d4 - () https://git.kernel.org/stable/c/4c22227e39c7a0b4dab55617ee8d34d171fab8d4 -
Summary
  • (es) En el kernel de Linux, se resolvió la siguiente vulnerabilidad: cfg80211: corrige el bloqueo de registros de administración. El bloqueo de registros de administración estaba roto, la lista estaba bloqueada para cada wdev, pero cfg80211_mgmt_registrations_update() la repitió sin mantener todos los spinlocks correctos, lo que provocó corrupción en la lista. En lugar de intentar solucionarlo con un bloqueo detallado, simplemente mueva el bloqueo a wiphy/rdev (aún necesitamos la lista en cada wdev), ya necesitamos mantener presionado el bloqueo wdev para cambiarlo, por lo que no hay contención en el bloqueo. En todo caso. Esto soluciona trivialmente el error ya que ya tenemos un bloqueo de wdev y ahora mantendremos el bloqueo que protege todas las listas.

22 May 2024, 09:15

Type Values Removed Values Added
New CVE
Information

Published : 2024-05-22 09:15

Updated : 2025-09-24 19:14

NVD link : CVE-2021-47494

Mitre link : CVE-2021-47494

CVE.ORG link : CVE-2021-47494

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-667

Improper Locking