CVE-2025-21703

Severity CVSS v4.0:

Pending analysis

Type:

CWE-416 Use After Free

Publication date:

18/02/2025

Last modified:

03/11/2025

Description

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.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 7.80 HIGH
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): High
Availability (A): High

Base Score 3.x

7.80

Severity 3.x

HIGH

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:o:linux:linux_kernel::::::::	5.4.288 (including)	5.4.291 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	5.10.232 (including)	5.10.235 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	5.15.175 (including)	5.15.179 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.1.121 (including)	6.1.129 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.6.67 (including)	6.6.78 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.12.6 (including)	6.12.14 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.13 (including)	6.13.3 (excluding)
cpe:2.3:o:linux:linux_kernel:6.14:rc1::::::

To consult the complete list of CPE names with products and versions, see this page

CVE-2025-21703

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools