CVE-2026-68122 ovpn: fix peer refcount leak in TCP error paths
A race condition in the Linux kernel OVPN module causes a peer reference count leak, potentially leading to memory exhaustion and denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-68122?
CVE-2026-68122 is a memory corruption vulnerability in Linux, published on 10 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:
ovpn: fix peer refcount leak in TCP error paths
When either the TCP RX or TX error path calls ovpn_peer_hold() followed by schedule_work(&peer->tcp.defer_del_work), and the work item is already pending from the other path, schedule_work() returns false and the work runs only once. Since ovpn_tcp_peer_del_work() calls ovpn_peer_put() exactly once, the extra reference taken by the losing path is never dropped, leaking the peer object.
The race window:
CPU0 (strparser/RX error): CPU1 (tcp_tx_work/TX error): ovpn_peer_hold() <- refcnt+1 ovpn_peer_hold() <- refcnt+2 schedule_work() <- queued schedule_work() <- NO-OP (work already pending) ovpn_tcp_peer_del_work runs: ovpn_peer_del() ovpn_peer_put() <- refcnt+1 <- peer never freed
Fix by checking the return value of schedule_work() in both paths and calling ovpn_peer_put() to drop the extra reference if the work was already pending. ovpn_peer_hold() is kept unconditional in the TX path as it cannot fail at that point.
Which versions are affected by CVE-2026-68122?
How do I fix CVE-2026-68122?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-68122 being exploited?
There is no known exploitation of CVE-2026-68122 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-68122, DEBIAN-CVE-2026-68122, GHSA-76xv-8vj7-3x63, UBUNTU-CVE-2026-68122.