CVE-2026-45389
HIGHOCaml-TLS < 2.1.0 - Client Certificate Impersonation via Insufficient KeyUsage Validation
Title source: llmDescription
In OCaml-TLS before 2.1.0, the server implementation does insufficient checks of the certificate provided by the client (when doing client authentication), which allows impersonation with certificates that are not meant for client authentication (because of KeyUsage and ExtendedKeyUsage).
References (1)
Core 1
Core References
Scores
CVSS v3
7.4
EPSS
0.0019
EPSS Percentile
9.0%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
total
Details
CWE
CWE-295
Status
published
Published
Jun 15, 2026
Tracked Since
Jun 16, 2026