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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-21971 Detail

Description

In the Linux kernel, the following vulnerability has been resolved: net_sched: Prevent creation of classes with TC_H_ROOT The function qdisc_tree_reduce_backlog() uses TC_H_ROOT as a termination condition when traversing up the qdisc tree to update parent backlog counters. However, if a class is created with classid TC_H_ROOT, the traversal terminates prematurely at this class instead of reaching the actual root qdisc, causing parent statistics to be incorrectly maintained. In case of DRR, this could lead to a crash as reported by Mingi Cho. Prevent the creation of any Qdisc class with classid TC_H_ROOT (0xFFFFFFFF) across all qdisc types, as suggested by Jamal.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://git.kernel.org/stable/c/003d92c91cdb5a64b25a9a74cb8543aac9a8bb48 kernel.org Patch 
https://git.kernel.org/stable/c/0c3057a5a04d07120b3d0ec9c79568fceb9c921e kernel.org Patch 
https://git.kernel.org/stable/c/5c3ca9cb48b51bd72bf76b8b05e24f3cd53db5e7 kernel.org Patch 
https://git.kernel.org/stable/c/78533c4a29ac3aeddce4b481770beaaa4f3bfb67 kernel.org Patch 
https://git.kernel.org/stable/c/7a82fe67a9f4d7123d8e5ba8f0f0806c28695006 kernel.org Patch 
https://git.kernel.org/stable/c/94edfdfb9505ab608e86599d1d1e38c83816fc1c kernel.org Patch 
https://git.kernel.org/stable/c/e05d9938b1b0ac40b6054cc5fa0ccbd9afd5ed4c kernel.org Patch 
https://git.kernel.org/stable/c/e5ee00607bbfc97ef1526ea95b6b2458ac9e7cb7 kernel.org Patch 
https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html CVE
https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html CVE

Weakness Enumeration

CWE-ID CWE Name Source
CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop') cwe source acceptance level NIST  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

4 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-21971
NVD Published Date:
04/01/2025
NVD Last Modified:
11/03/2025
Source:
kernel.org