What is CVE-2026-50721?

CVE-2026-50721 is a high-severity vulnerability in The Libreswan Project, classified under Improper Verification of Cryptographic Signature. CVSS score: 8.1/10. Published 2026-07-02.

How severe is CVE-2026-50721?

High severity. CVSS v3 base score is 8.1 out of 10.

Vulnerability in The Libreswan Project

CVE-2026-50721

Libreswan, via the function RSA_authenticate_hash_signature_raw_rsa(), did not correctly verify the length of the authentication hash when the SIG payload of an IKEv1 packet was encoded using PKCS #1 RSA Encryption as per RFC 2313. A remot…

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

The Libreswan Project — versions 0, 5.3.1

Weakness classification (CWE)

References

d42dc95b-23f1-4e06-9076-20753a0fb0df (vendor-advisory)
d42dc95b-23f1-4e06-9076-20753a0fb0df (patch)
d42dc95b-23f1-4e06-9076-20753a0fb0df (related)
d42dc95b-23f1-4e06-9076-20753a0fb0df (technical-description)

Frequently asked questions

What is CVE-2026-50721?: CVE-2026-50721 is a high-severity vulnerability in The Libreswan Project, classified under Improper Verification of Cryptographic Signature. CVSS score: 8.1/10. Published 2026-07-02.
How severe is CVE-2026-50721?: High severity. CVSS v3 base score is 8.1 out of 10.