Medium [CVE-2026-53079] fix skb memory leak in deferred qdisc drops
This medium-severity Red Hat Linux advisory covers CVE-2026-53079.
Android app · Google Play
Monitor future Red Hat Linux CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
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.
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.
A flaw was found in the Linux kernel's networking scheduler (`net_sched`). When the network stack cleans up deferred packet lists, if the root queueing discipline (qdisc) does not implement the TCQ_F_DEQUEUE_DROPS flag, packets intended for release are not freed.
This can lead to a memory leak, potentially resulting in a Denial of Service (DoS) due to resource exhaustion. Red Hat severity: Moderate.
Weakness: CWE-772. Red Hat lists Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9 as not affected.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · medium-confidence parse· fetched 9 days ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists — confirm against the vendor advisory.
Official advisory · medium-confidence parse· fetched 9 days ago·verify at source
Mitigation
The source record does not include mitigation steps. That is not a statement that no fix exists — read the vendor advisory below for the authoritative guidance.
Official advisory · medium-confidence parse· fetched 9 days ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.