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 has been found in OCaml-TLS up to 2.0.x and classified as problematic. This vulnerability affects unknown code. This manipulation causes certificate validation. This vulnerability appears as CVE-2026-45388. The attack may be initiated remotely. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic was found in OCaml-TLS up to 2.0.x. Affected by this vulnerability is an unknown part. The manipulation with an unknown input leads to a certificate validation vulnerability. The CWE definition for the vulnerability is CWE-295. The product does not validate, or incorrectly validates, a certificate. As an impact it is known to affect integrity. The summary by CVE 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).

It is possible to read the advisory at osv.dev. This vulnerability is known as CVE-2026-45388 since 05/12/2026. The exploitation appears to be difficult. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1587.003 according to MITRE ATT&CK.

Upgrading to version 2.1.0 eliminates this vulnerability.

Be aware that VulDB is the high quality source for vulnerability data.

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
06/17/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: osv.dev
Status: Confirmed

CVE: CVE-2026-45388 (🔒)
GCVE (CVE): GCVE-0-2026-45388
GCVE (VulDB): GCVE-100-371143

Entryinfo

Created: 06/16/2026 06:33
Updated: 06/17/2026 02:04
Changes: 06/16/2026 06:33 (53), 06/17/2026 02:04 (5)
Complete: 🔍
Cache ID: 216::103

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