CVE-2026-98604 ovpn: replace bind when learning local endpoint
A race condition in the Linux kernel OVPN module allows concurrent updates to cause torn address reads, potentially leading to denial of service or information disclosure.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-98604?
CVE-2026-98604 is a vulnerability in Linux, published on 18 Oct 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: replace bind when learning local endpoint
struct ovpn_bind is published through peer->bind with RCU, but local endpoint learning updates bind->local in place under peer->lock. UDP TX reads the field without that lock. In particular, a concurrent IPv6 update can therefore result in a torn address read.
Use ovpn_peer_reset_sockaddr to publish a replacement bind when learning a new local endpoint, just as a remote endpoint change does. Preserve the current remote address and reset the dst cache only after the new bind has been published successfully.
Track remote endpoint changes separately so that float notification and transport-address rehashing remain limited to actual peer floats.
Which versions are affected by CVE-2026-98604?
How do I fix CVE-2026-98604?
Apply the vendor's patch.
Is CVE-2026-98604 being exploited?
There is no known exploitation of CVE-2026-98604 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-98604, DEBIAN-CVE-2026-98604, GHSA-hmmp-5rq5-qfff, UBUNTU-CVE-2026-98604.