CVE-2026-74708 xsk: validate launch-time metadata size
The Linux kernel XSK subsystem fails to validate metadata size and flags, potentially allowing local attackers to cause memory corruption or privilege escalation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74708?
CVE-2026-74708 is a high-severity missing authorization vulnerability in Linux, published on 22 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: validate launch-time metadata size
Launch-time metadata extends beyond the first 16 bytes of struct xsk_tx_metadata. Reject the request when the registered metadata area does not contain the complete field.
Snapshot the validated flags for the generic transmit path and use that snapshot for request and completion processing, avoiding inconsistent decisions if user space changes the flags concurrently.
Note that only xsk_skb_metadata is properly using the flags, __xsk_buff_get_metadata ignores them. Next commits address that.
Which versions are affected by CVE-2026-74708?
How do I fix CVE-2026-74708?
Apply the vendor's patch.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-74708 being exploited?
There is no known exploitation of CVE-2026-74708 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-74708, DEBIAN-CVE-2026-74708, GHSA-qvq6-8jqj-q3p2, UBUNTU-CVE-2026-74708.