CVE-2026-80681 vxlan: re-fetch eth header after route_shortcircuit()
A use-after-free in the Linux kernel VXLAN driver allows attackers to potentially execute code or escalate privileges via crafted network packets.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-80681?
CVE-2026-80681 is a critical use after free vulnerability in Linux, published on 28 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
vxlan: re-fetch eth header after route_shortcircuit()
Before route_shortcircuit(), the eth header pointer is cached from eth_hdr(skb).
Inside route_shortcircuit(), pskb_may_pull() can be called, which may reallocate skb->head.
In this case, returning to vxlan_xmit() leaves the cached eth pointer pointing to freed memory, leading to a use-after-free when dereferencing eth->h_dest.
Fix this by updating eth = eth_hdr(skb) after calling route_shortcircuit().
Which versions are affected by CVE-2026-80681?
How do I fix CVE-2026-80681?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-80681 being exploited?
There is no known exploitation of CVE-2026-80681 in the wild and no public exploit code.
Sources
Also known as AZL-98114, BELL-CVE-2026-80681, DEBIAN-CVE-2026-80681, GHSA-6mmh-5qqr-f237, UBUNTU-CVE-2026-80681.