CVE-2026-80681
CRITICAL 9.8In 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().
Severe if exploited (CVSS 9.8), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.2%chance of exploitation in 30 days · 7th percentile
Impact if exploited
9.8CVSS 3.1 · CRITICAL
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityHigh
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-80681/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-80681/poc.json
Weakness (CWE)
Not classified.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
Technical & other
- https://git.kernel.org/stable/c/6375093eb45cd7d89f1945f939eeae3b29d79f56
- https://git.kernel.org/stable/c/1b7f7b653e3557690047c62f03b80a24ea5a58a5
- https://git.kernel.org/stable/c/bf045341dfb3e767f0ff94cf240ce3c371973bd4
- https://git.kernel.org/stable/c/2355c8c26d2aa1b4385b369e67202e47d460d555
- https://git.kernel.org/stable/c/1511631b7cfc4152b10a0a9d04c7a0bf2ddf4585
- https://git.kernel.org/stable/c/1235e017aa11cf01e91b613c4c5ed6aa28934fff
- https://git.kernel.org/stable/c/c9dceac9e1c7c772c43c732fc0d325e72835801a
- https://git.kernel.org/stable/c/1395a676ec15a0a02a2a6d86602324f2d5fd41d5