A flaw was found in OpenSSL. When configured to use an RSA key with exponent 3, OpenSSL improperly removes PKCS-1 padding before generating a hash. This allows remote attackers to forge PKCS #1 v1.5 signatures. Consequently, OpenSSL may incorrectly verify X.509 and other certificates, leading to a bypass of trust and authentication mechanisms.
CVE-2006-4339
CVSS base score
9.1 (v3.1)
Severity
CRITICAL
Attack vector
Network
Weakness
CWE-347, CWE-310
Last modified
October 30, 2026
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products
openssl openssl