What is CVE-2025-3757?

CVE-2025-3757 is a critical-severity vulnerability in Openpubkey, classified under Authentication Bypass by Primary Weakness. CVSS score: 9.8/10. Published 2025-05-13.

How severe is CVE-2025-3757?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Openpubkey

CVE-2025-3757

Versions of OpenPubkey library prior to 0.10.0 contained a vulnerability that would allow a specially crafted JWS to bypass signature verification.

EPSS: 0.004 (27.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Openpubkey
Opkssh — versions Openpubkey

Weakness classification (CWE)

CWE-305 — Authentication Bypass by Primary Weakness
CWE-347 — Improper Verification of Cryptographic Signature

References

cna@cloudflare.com (Product)

Frequently asked questions

What is CVE-2025-3757?: CVE-2025-3757 is a critical-severity vulnerability in Openpubkey, classified under Authentication Bypass by Primary Weakness. CVSS score: 9.8/10. Published 2025-05-13.
How severe is CVE-2025-3757?: Critical severity. CVSS v3 base score is 9.8 out of 10.