CVE-2018-16151

In verify_emsa_pkcs1_signature() in gmp_rsa_public_key.c in the gmp plugin in strongSwan 4.x and 5.x before 5.7.0, the RSA implementation based on GMP does not reject excess data after the encoded algorithm OID during PKCS#1 v1.5 signature verification. Similar to the flaw in the same version of strongSwan regarding digestAlgorithm.parameters, a remote attacker can forge signatures when small public exponents are being used, which could lead to impersonation when only an RSA signature is used for IKEv2 authentication.

Score

CVSS 3.1 7.5 High

Status

Modified - cve@mitre.org

Published

2018-09-26

Last modified

2025-12-03

Weaknesses

CWE-347

Affected products

• Ubuntu Linux (Canonical)
• Debian Linux (Debian)
• Strongswan (Strongswan)

References

• http://lists.opensuse.org/opensuse-security-announce/2019-11/msg00077.html
• http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00001.html
• http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00047.html
• https://lists.debian.org/debian-lts-announce/2018/09/msg00032.html
• https://security.gentoo.org/glsa/201811-16
• https://usn.ubuntu.com/3771-1/
• https://www.debian.org/security/2018/dsa-4305
• https://www.strongswan.org/blog/2018/09/24/strongswan-vulnerability-%28cve-2018-16151%2C-cve-2018-16152%29.html