VULNERABILITY INTELLIGENCE

CVE-2018-16253

CVSS score5.9 MEDIUM

EPSS probability0.62%

CISA KEVNot currently listed

Published2018-11-07

Last modified2026-06-17

CVSS vectorCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Description

In sig_verify() in x509.c in axTLS version 2.1.3 and before, the PKCS#1 v1.5 signature verification does not properly verify the ASN.1 metadata. Consequently, a remote attacker can forge signatures when small public exponents are being used, which could lead to impersonation through fake X.509 certificates. This is an even more permissive variant of CVE-2006-4790 and CVE-2014-1568.

Weakness classification

CWE-347: Improper Verification of Cryptographic Signature

Primary references

cve@mitre.org — Patch, Third Party Advisory
cve@mitre.org — Exploit, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108 — Exploit, Third Party Advisory