CVE-2026-87733: CWE-295 Improper Certificate Validation in OCaml mirage-crypto-ec
Description
A vulnerability in the mirage-crypto-ec library for OCaml versions before 2.2.0 allows improper certificate validation. The ECDSA functions for P256, P384, and P521 curves accept the encoding of the point at infinity (0x00) as a valid public key. This flaw enables forging signatures without possessing the private key.
CVSS v3.1
6.2medium
Affected software
OCaml
mirage-crypto-ec
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-87733 is an improper certificate validation vulnerability (CWE-295) in the mirage-crypto-ec library for OCaml. Specifically, the ECDSA functions {P256,P384,P521}.Dsa.pub_of_octets incorrectly accept 0x00, the encoding of the point at infinity, as a valid public key. This acceptance allows an attacker to forge signatures without the corresponding private key. The issue affects all versions prior to 2.2.0.
Potential Impact
An attacker can forge digital signatures without access to the private key, compromising the integrity of cryptographic operations relying on the affected ECDSA functions. This can lead to unauthorized actions being accepted as validly signed, impacting systems that use this library for cryptographic verification.
Mitigation Recommendations
A fix is available in mirage-crypto-ec version 2.2.0 and later. Users should upgrade to version 2.2.0 or newer to remediate this vulnerability. No vendor advisory content was provided to indicate alternative mitigations or temporary fixes.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 09/09/2026
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6aa0e2c5acd9273b49baa908
Added to database: 09/09/2026, 04:38:29 UTC
Last enriched: 10/17/2026, 23:22:36 UTC
Last updated: 10/24/2026, 08:45:13 UTC
Views: 101
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