CVE-2025-21703

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2025-21703
In the Linux kernel, the following vulnerability has been resolved: netem: Update sch->q.qlen before qdisc_tree_reduce_backlog() qdisc_tree_reduce_backlog() notifies parent qdisc only if child qdisc becomes empty, therefore we need to reduce the backlog of the child qdisc before calling it. Otherwise it would miss the opportunity to call cops->qlen_notify(), in the case of DRR, it resulted in UAF since DRR uses ->qlen_notify() to maintain its active list.

7.8 /10

CVSS v3 : HIGH

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://git.kernel.org/stable/c/1f8e3f4a4b8b90ad274dfbc66fc7d55cb582f4d5 Patch
https://git.kernel.org/stable/c/6312555249082d6d8cc5321ff725df05482d8b83 Patch
https://git.kernel.org/stable/c/638ba5089324796c2ee49af10427459c2de35f71 Patch
https://git.kernel.org/stable/c/7b79ca9a1de6a428d486ff52fb3d602321c08f55 Patch
https://git.kernel.org/stable/c/7f31d74fcc556a9166b1bb20515542de7bb939d1 Patch
https://git.kernel.org/stable/c/839ecc583fa00fab785fde1c85a326743657fd32 Patch
https://git.kernel.org/stable/c/98a2c685293aae122f688cde11d9334dddc5d207 Patch
https://git.kernel.org/stable/c/e395fec75ac2dbffc99b4bce57b7f1f3c5449f2c 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:6.14:rc1:*:*:*:*:*:*
History

24 Mar 2025, 17:38

Type Values Removed Values Added
References () https://git.kernel.org/stable/c/1f8e3f4a4b8b90ad274dfbc66fc7d55cb582f4d5 - () https://git.kernel.org/stable/c/1f8e3f4a4b8b90ad274dfbc66fc7d55cb582f4d5 - Patch
References () https://git.kernel.org/stable/c/6312555249082d6d8cc5321ff725df05482d8b83 - () https://git.kernel.org/stable/c/6312555249082d6d8cc5321ff725df05482d8b83 - Patch
References () https://git.kernel.org/stable/c/638ba5089324796c2ee49af10427459c2de35f71 - () https://git.kernel.org/stable/c/638ba5089324796c2ee49af10427459c2de35f71 - Patch
References () https://git.kernel.org/stable/c/7b79ca9a1de6a428d486ff52fb3d602321c08f55 - () https://git.kernel.org/stable/c/7b79ca9a1de6a428d486ff52fb3d602321c08f55 - Patch
References () https://git.kernel.org/stable/c/7f31d74fcc556a9166b1bb20515542de7bb939d1 - () https://git.kernel.org/stable/c/7f31d74fcc556a9166b1bb20515542de7bb939d1 - Patch
References () https://git.kernel.org/stable/c/839ecc583fa00fab785fde1c85a326743657fd32 - () https://git.kernel.org/stable/c/839ecc583fa00fab785fde1c85a326743657fd32 - Patch
References () https://git.kernel.org/stable/c/98a2c685293aae122f688cde11d9334dddc5d207 - () https://git.kernel.org/stable/c/98a2c685293aae122f688cde11d9334dddc5d207 - Patch
References () https://git.kernel.org/stable/c/e395fec75ac2dbffc99b4bce57b7f1f3c5449f2c - () https://git.kernel.org/stable/c/e395fec75ac2dbffc99b4bce57b7f1f3c5449f2c - Patch
First Time Linux linux Kernel
Linux
CPE cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

13 Mar 2025, 13:15

Type Values Removed Values Added
References
  • () https://git.kernel.org/stable/c/7f31d74fcc556a9166b1bb20515542de7bb939d1 -
  • () https://git.kernel.org/stable/c/98a2c685293aae122f688cde11d9334dddc5d207 -
  • () https://git.kernel.org/stable/c/e395fec75ac2dbffc99b4bce57b7f1f3c5449f2c -

21 Feb 2025, 14:15

Type Values Removed Values Added
References
  • () https://git.kernel.org/stable/c/7b79ca9a1de6a428d486ff52fb3d602321c08f55 -
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netem: Actualizar sch->q.qlen antes de qdisc_tree_reduce_backlog() qdisc_tree_reduce_backlog() notifica a la qdisc principal solo si la qdisc secundaria se vacía, por lo tanto, debemos reducir el backlog de la qdisc secundaria antes de llamarla. De lo contrario, perdería la oportunidad de llamar a cops->qlen_notify(), en el caso de DRR, resultó en UAF ya que DRR usa ->qlen_notify() para mantener su lista activa.

18 Feb 2025, 16:15

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 7.8
CWE CWE-416

18 Feb 2025, 15:15

Type Values Removed Values Added
New CVE
Information

Published : 2025-02-18 15:15

Updated : 2025-03-24 17:38

NVD link : CVE-2025-21703

Mitre link : CVE-2025-21703

CVE.ORG link : CVE-2025-21703

JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-416

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