Medium [CVE-2026-74559] drain continuation descs after overflow in xsk_build_skb
This medium-severity Red Hat Linux advisory covers CVE-2026-74559.
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: xsk: drain continuation descs after overflow in xsk_build_skb() Fix generic xmit path multi-buffer logic when packets are either too big (count of descriptors exceed MAX_SKB_FRAGS) or an invalid descriptor is included in fragmented packet.
Introduce xdp_sock::drain_cont and act upon this flag - when it is set, keep on consuming descriptors from AF_XDP Tx ring and put them directly onto Cq. Previously these descriptors were silently lost and could never be reached again.
A flaw was found in the Linux kernel's AF_XDP (eXpress Data Path) networking component. This vulnerability, located in the `xsk_build_skb()` function, involves improper handling of network packet descriptors.
When processing large or malformed multi-buffer packets, the system fails to properly drain continuation descriptors after an overflow, leading to their silent loss. An attacker could exploit this issue by sending specially crafted packets, resulting in a denial of service that impacts network communication.
Red Hat severity: Low — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-772.
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 1 hour 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 1 hour 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 1 hour 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.