CVE-2026-45388

In OCaml-TLS before 2.1.0, the client implementation does insufficient checks of the certificate provided by the server, which allows impersonation with…

Critical · published June 15, 2026

CVSS v3.1
9.1
EPSS
0%
Percentile
23.0
In the wild
Unconfirmed
What it is

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).

The record
Technical detail
CVSS v3.1
9.1 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00313 · 23.0th percentile
Published
2026-06-15T00:00Z
EPSS history
Timeline
  • 15 JUN 00:00Z
    In OCaml-TLS before 2.1.0, the client implementation does insufficient checks of the certificate provided by the server, which allows impersonation with…
    cvelistv5