CVE-2026-74559 xsk: drain continuation descs after overflow in xsk_build_skb()
A flaw in the Linux kernel's AF_XDP transmit path causes descriptor loss on overflow, leading to potential denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74559?
CVE-2026-74559 is a denial of service vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-74559?
How do I fix CVE-2026-74559?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-74559 being exploited?
There is no known exploitation of CVE-2026-74559 in the wild and no public exploit code.
Sources
Also known as AZL-96483, BELL-CVE-2026-74559, DEBIAN-CVE-2026-74559, GHSA-9hgr-2c8j-c3h6, UBUNTU-CVE-2026-74559.