CVE-2026-45929 ovpn: fix possible use-after-free in ovpn_net_xmit
A use-after-free vulnerability in the Linux kernel's ovpn module allows attackers to potentially execute code or cause a denial of service.
- 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-2026-45929?
CVE-2026-45929 is a high-severity use after free vulnerability in Linux kernel, published on 27 May 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:
ovpn: fix possible use-after-free in ovpn_net_xmit
When building the skb_list in ovpn_net_xmit, skb_share_check will free the original skb if it is shared. The current implementation continues to use the stale skb pointer for subsequent operations: - peer lookup, - skb_dst_drop (even though all segments produced by skb_gso_segment will have a dst attached), - ovpn_peer_stats_increment_tx.
Fix this by moving the peer lookup and skb_dst_drop before segmentation so that the original skb is still valid when used. Return early if all segments fail skb_share_check and the list ends up empty. Also switch ovpn_peer_stats_increment_tx to use skb_list.next; the next patch fixes the stats logic.
Weakness: CWE-416
Which versions are affected by CVE-2026-45929?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-45929?
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-2026-45929 being exploited?
There is no known exploitation of CVE-2026-45929 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-45929, DEBIAN-CVE-2026-45929, GHSA-54qr-3h8v-g6xr, UBUNTU-CVE-2026-45929.