CVE-2021-47294

  1. Yack CVE
  2. Vulnerabilities (CVE)
  3. CVE-2021-47294

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

I

n the Linux kernel, the following vulnerability has been resolved: netrom: Decrease sock refcount when sock timers expire Commit 63346650c1a9 ("netrom: switch to sock timer API") switched to use sock timer API. It replaces mod_timer() by sk_reset_timer(), and del_timer() by sk_stop_timer(). Function sk_reset_timer() will increase the refcount of sock if it is called on an inactive timer, hence, in case the timer expires, we need to decrease the refcount ourselves in the handler, otherwise, the sock refcount will be unbalanced and the sock will never be freed.

References
Link Resource
https://git.kernel.org/stable/c/25df44e90ff5959b5c24ad361b648504a7e39ef3 Patch
https://git.kernel.org/stable/c/48866fd5c361ea417ed24b43fc2a7dc2f5b060ef Patch
https://git.kernel.org/stable/c/517a16b1a88bdb6b530f48d5d153478b2552d9a8 Patch
https://git.kernel.org/stable/c/6811744bd0efb9e472cb15d066cdb460beb8cb8a Patch
https://git.kernel.org/stable/c/853262355518cd1247515b74e83fabf038aa6c29 Patch
https://git.kernel.org/stable/c/9619cc7d97c3aa8ed3cfd2b8678b74fb6d6c7950 Patch
https://git.kernel.org/stable/c/a01634bf91f2b6c42583770eb6815fb6d1e251cf Patch
https://git.kernel.org/stable/c/bc1660206c3723c37ed4d622ad81781f1e987250 Patch
https://git.kernel.org/stable/c/25df44e90ff5959b5c24ad361b648504a7e39ef3 Patch
https://git.kernel.org/stable/c/48866fd5c361ea417ed24b43fc2a7dc2f5b060ef Patch
https://git.kernel.org/stable/c/517a16b1a88bdb6b530f48d5d153478b2552d9a8 Patch
https://git.kernel.org/stable/c/6811744bd0efb9e472cb15d066cdb460beb8cb8a Patch
https://git.kernel.org/stable/c/853262355518cd1247515b74e83fabf038aa6c29 Patch
https://git.kernel.org/stable/c/9619cc7d97c3aa8ed3cfd2b8678b74fb6d6c7950 Patch
https://git.kernel.org/stable/c/a01634bf91f2b6c42583770eb6815fb6d1e251cf Patch
https://git.kernel.org/stable/c/bc1660206c3723c37ed4d622ad81781f1e987250 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:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:3.18.134:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:4.20.7:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.14:rc2:*:*:*:*:*:*
History

23 Jun 2025, 20:19

Type Values Removed Values Added
CPE cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.14:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:4.20.7:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:3.18.134:*:*:*:*:*:*:*
References () https://git.kernel.org/stable/c/25df44e90ff5959b5c24ad361b648504a7e39ef3 - () https://git.kernel.org/stable/c/25df44e90ff5959b5c24ad361b648504a7e39ef3 - Patch
References () https://git.kernel.org/stable/c/48866fd5c361ea417ed24b43fc2a7dc2f5b060ef - () https://git.kernel.org/stable/c/48866fd5c361ea417ed24b43fc2a7dc2f5b060ef - Patch
References () https://git.kernel.org/stable/c/517a16b1a88bdb6b530f48d5d153478b2552d9a8 - () https://git.kernel.org/stable/c/517a16b1a88bdb6b530f48d5d153478b2552d9a8 - Patch
References () https://git.kernel.org/stable/c/6811744bd0efb9e472cb15d066cdb460beb8cb8a - () https://git.kernel.org/stable/c/6811744bd0efb9e472cb15d066cdb460beb8cb8a - Patch
References () https://git.kernel.org/stable/c/853262355518cd1247515b74e83fabf038aa6c29 - () https://git.kernel.org/stable/c/853262355518cd1247515b74e83fabf038aa6c29 - Patch
References () https://git.kernel.org/stable/c/9619cc7d97c3aa8ed3cfd2b8678b74fb6d6c7950 - () https://git.kernel.org/stable/c/9619cc7d97c3aa8ed3cfd2b8678b74fb6d6c7950 - Patch
References () https://git.kernel.org/stable/c/a01634bf91f2b6c42583770eb6815fb6d1e251cf - () https://git.kernel.org/stable/c/a01634bf91f2b6c42583770eb6815fb6d1e251cf - Patch
References () https://git.kernel.org/stable/c/bc1660206c3723c37ed4d622ad81781f1e987250 - () https://git.kernel.org/stable/c/bc1660206c3723c37ed4d622ad81781f1e987250 - Patch
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.5
First Time Linux linux Kernel
Linux
CWE CWE-672

21 Nov 2024, 06:35

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se resolvió la siguiente vulnerabilidad: netrom: Disminuir el recuento de sock cuando caducan los temporizadores de sock. La confirmación 63346650c1a9 ("netrom: cambiar a API de temporizador de sock") cambió para usar la API de temporizador de sock. Reemplaza mod_timer() por sk_reset_timer() y del_timer() por sk_stop_timer(). La función sk_reset_timer() aumentará el recuento del sock si se llama en un temporizador inactivo, por lo tanto, en caso de que el temporizador expire, debemos disminuir el recuento nosotros mismos en el controlador; de lo contrario, el recuento del calcetín se desequilibrará y el sock nunca será liberado.
References () https://git.kernel.org/stable/c/25df44e90ff5959b5c24ad361b648504a7e39ef3 - () https://git.kernel.org/stable/c/25df44e90ff5959b5c24ad361b648504a7e39ef3 -
References () https://git.kernel.org/stable/c/48866fd5c361ea417ed24b43fc2a7dc2f5b060ef - () https://git.kernel.org/stable/c/48866fd5c361ea417ed24b43fc2a7dc2f5b060ef -
References () https://git.kernel.org/stable/c/517a16b1a88bdb6b530f48d5d153478b2552d9a8 - () https://git.kernel.org/stable/c/517a16b1a88bdb6b530f48d5d153478b2552d9a8 -
References () https://git.kernel.org/stable/c/6811744bd0efb9e472cb15d066cdb460beb8cb8a - () https://git.kernel.org/stable/c/6811744bd0efb9e472cb15d066cdb460beb8cb8a -
References () https://git.kernel.org/stable/c/853262355518cd1247515b74e83fabf038aa6c29 - () https://git.kernel.org/stable/c/853262355518cd1247515b74e83fabf038aa6c29 -
References () https://git.kernel.org/stable/c/9619cc7d97c3aa8ed3cfd2b8678b74fb6d6c7950 - () https://git.kernel.org/stable/c/9619cc7d97c3aa8ed3cfd2b8678b74fb6d6c7950 -
References () https://git.kernel.org/stable/c/a01634bf91f2b6c42583770eb6815fb6d1e251cf - () https://git.kernel.org/stable/c/a01634bf91f2b6c42583770eb6815fb6d1e251cf -
References () https://git.kernel.org/stable/c/bc1660206c3723c37ed4d622ad81781f1e987250 - () https://git.kernel.org/stable/c/bc1660206c3723c37ed4d622ad81781f1e987250 -

21 May 2024, 15:15

Type Values Removed Values Added
New CVE
Information

Published : 2024-05-21 15:15

Updated : 2025-06-23 20:19

NVD link : CVE-2021-47294

Mitre link : CVE-2021-47294

CVE.ORG link : CVE-2021-47294

JSON object : View

Products Affected

linux

CWE
CWE-672

Operation on a Resource after Expiration or Release