OCaml-TLS up to 2.0.x certificate validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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3.6$0-$5k0.00

Summaryinfo

A vulnerability was found in OCaml-TLS up to 2.0.x and classified as problematic. This issue affects some unknown processing. Such manipulation leads to certificate validation. This vulnerability is traded as CVE-2026-45389. The attack may be launched remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in OCaml-TLS up to 2.0.x. Affected by this issue is an unknown code. The manipulation with an unknown input leads to a certificate validation vulnerability. Using CWE to declare the problem leads to CWE-295. The product does not validate, or incorrectly validates, a certificate. Impacted is integrity. CVE summarizes:

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).

The advisory is shared for download at osv.dev. This vulnerability is handled as CVE-2026-45389 since 05/12/2026. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1587.003.

Upgrading to version 2.1.0 eliminates this vulnerability.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.7
VulDB Meta Temp Score: 3.6

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Certificate validation
CWE: CWE-295 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: OCaml-TLS 2.1.0

Timelineinfo

05/12/2026 CVE reserved
06/16/2026 +35 days Advisory disclosed
06/16/2026 +0 days VulDB entry created
06/16/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: osv.dev
Status: Confirmed

CVE: CVE-2026-45389 (🔒)
GCVE (CVE): GCVE-0-2026-45389
GCVE (VulDB): GCVE-100-371144

Entryinfo

Created: 06/16/2026 06:33
Changes: 06/16/2026 06:33 (53)
Complete: 🔍
Cache ID: 216::103

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