Description
In the Linux kernel, the following vulnerability has been resolved: codel: remove sch->q.qlen check before qdisc_tree_reduce_backlog() After making all ->qlen_notify() callbacks idempotent, now it is safe to remove the check of qlen!=0 from both fq_codel_dequeue() and codel_qdisc_dequeue().
Affected products
linux: linux kernel; debian: debian linux
References10
- git.kernel.org/stable/c/2f9761a94bae33d26e6a81b31b36e7d776d93dc1 Patch
- git.kernel.org/stable/c/342debc12183b51773b3345ba267e9263bdfaaef Patch
- git.kernel.org/stable/c/4d55144b12e742404bb3f8fee6038bafbf45619d Patch
- git.kernel.org/stable/c/7a742a9506849d1c1aa71e36c89855ceddc7d58e Patch
- git.kernel.org/stable/c/829c49b6b2ff45b043739168fd1245e4e1a91a30 Patch
- git.kernel.org/stable/c/a57fe60ef4cf96bfbb6b58397ec28bdb5a5c6b31 Patch
- git.kernel.org/stable/c/cc71a757da78dd4aa1b4a9b19cb011833730ccf2 Patch
- git.kernel.org/stable/c/e73c838c80dccb9e4f19becc11d9f3cb4a27d483 Patch
- git.kernel.org/stable/c/eda741fe155ddf5ecd2dd3bfbd4fc3c0c7dbb450 Patch
- lists.debian.org/debian-lts-announce/2025/05/msg00045.html Issue TrackingThird Party Advisory
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 14 · as of 7 November 2026
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.