CVE-2026-45388: OCaml-TLS versions before 2.1.0 have a
Source CVE Database V5
Not known to be exploited · CVSS 9.1 Critical · fixed in 2.1.0 : patch affected systems as a priority.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 13% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2.1.0
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 15 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
AI-suggested
If you cannot patch yet, avoid using vulnerable versions in security-critical environments or implement additional certificate validation checks externally if possible.
Description
OCaml-TLS versions before 2.1.0 have a vulnerability in the client implementation where insufficient checks are performed on server certificates. This flaw allows an attacker to impersonate a server using certificates that lack proper KeyUsage and ExtendedKeyUsage attributes for server authentication. The vulnerability is critical with a CVSS score of 9.1, indicating high impact on confidentiality and integrity without requiring privileges or user interaction.