Linux Kernel up to 7.0.9 net_sched qdisc_run_end memory leak

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 7.0.9. This impacts the function qdisc_run_end of the component net_sched. The manipulation results in memory leak. This vulnerability is cataloged as CVE-2026-53079. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 7.0.9. Affected is the function qdisc_run_end of the component net_sched. The manipulation with an unknown input leads to a memory leak vulnerability. CWE is classifying the issue as CWE-401. The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net_sched: fix skb memory leak in deferred qdisc drops When the network stack cleans up the deferred list via qdisc_run_end(), it operates on the root qdisc. If the root qdisc do not implement the TCQ_F_DEQUEUE_DROPS flag the packets queue to free are never freed and gets stranded on the child's local to_free list. Fix this by making qdisc_dequeue_drop() aware of the root qdisc. It fetches the root qdisc and check for the TCQ_F_DEQUEUE_DROPS flag. If the flag is present, the packet is appended directly to the root's to_free list. Otherwise, drop it directly as it was done before the optimization was implemented.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2026-53079 since 06/09/2026. The exploitability is told to be easy. There are known technical details, but no exploit is available.

Upgrading to version 7.0.10 eliminates this vulnerability. Applying the patch bf26ad92ffda7884825d67b46bd5efe615c3babf/a6bd339dbb3514bce690fdcf252e788dfab4ee76 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 7.0.0
• 7.0.1
• 7.0.2
• 7.0.3
• 7.0.4
• 7.0.5
• 7.0.6
• 7.0.7
• 7.0.8
• 7.0.9

License

• open-source

Website

• Vendor: https://www.kernel.org/

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