What is CVE-2026-87733?

CVE-2026-87733 is a medium-severity vulnerability, classified under Improper Certificate Validation. CVSS score: 6.2/10. Published 2026-09-09.

How severe is CVE-2026-87733?

Medium severity. CVSS v3 base score is 6.2 out of 10.

CVE-2026-87733

CVE-2026-87733

An issue was discovered in the mirage-crypto-ec function before 2.2.0 for OCaml. The ECDSA functions {P256,P384,P521}.Dsa.pub_of_octets accept 0x00, the encoding of the point at infinity, as a public key. With that public key, signatures can be forged without a private key.

Vulnerability class: Improper Certificate Validation

CVSS v3 metric

CVSS v3 base score 6.2 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

Weakness classification (CWE)

CWE-295 — Improper Certificate Validation

References

cve@mitre.org

Frequently asked questions

What is CVE-2026-87733?: CVE-2026-87733 is a medium-severity vulnerability, classified under Improper Certificate Validation. CVSS score: 6.2/10. Published 2026-09-09.
How severe is CVE-2026-87733?: Medium severity. CVSS v3 base score is 6.2 out of 10.