Vulnerability · Published Jun 15, 2026 · Assigned by mitre
CVE-2026-45388
Critical 9.1
In plain English
A critical-severity improper certificate validation in the affected software. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities).
Severity (CVSS 3.1)9.1Critical
Exploit odds (30 days)0.2%top 86.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
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).
Affected products (as reported)
Weakness: CWE-295 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N