CVE-2026-45388 Security feature bypass in n/a
Insufficient certificate checks in OCaml-TLS allow server impersonation using certificates not intended for server authentication.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45388?
CVE-2026-45388 is a critical vulnerability in n/a, published on 15 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In OCaml-TLS before 2.1.0, the client implementation does insufficient checks of the certificate provided by the server, which allows impersonation with certificates that are not meant for server authentication (because of KeyUsage and ExtendedKeyUsage).
Weakness: CWE-295
Which versions are affected by CVE-2026-45388?
How do I fix CVE-2026-45388?
Upgrade to a fixed version.
Is CVE-2026-45388 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45388 exists.
Sources
Also known as GHSA-rrgx-wgv5-5hf9, OSEC-2026-06.