CVE-2006-4339

Red Hat Enterprise Linux 3 · Vulnerability

CVSS 3.1 9.1 CRITICALCheck source for fixed versionsKEV status unknown

Original advisory

cve-program · CVE-2006-4339

Published

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.

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Affected versions, risk and source history

Exploitation and risk

Source status

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Risk history

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Advisory history

3 saved versions

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4 Nov 2026 20:54:02 UTC

Openssl: openssl: signature forgery via improper pkcs-1 padding removal leading to certificate validation bypass

cve-program · CVE-2006-4339 · Published

30 Oct 2026 17:45:26 UTC

Openssl: openssl: signature forgery via improper pkcs-1 padding removal leading to certificate validation bypass

cve-program · CVE-2006-4339 · Published

23 Oct 2026 15:48:27 UTC

OpenSSL before 0.9.7, 0.9.7 before 0.9.7k, and 0.9.8 before 0.9.8c, when using an RSA key with exponent 3, removes PKCS-1 padding before generating a hash, which allows remote attackers to forge a PKCS #1 v1.5 signature that is signed by th…

cve-program · CVE-2006-4339 · Published