CVE Catalog

CVE-2022-4304

MediumCVSS 5.9
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Very high risk
16.20%

97th percentile - higher than 97% of all known CVEs

Summary

A timing based side channel exists in the OpenSSL RSA Decryption implementation which could be sufficient to recover a plaintext across a network in a Bleichenbacher style attack. To achieve a successful decryption an attacker would have to be able to send a very large number of trial messages for decryption. The vulnerability affects all RSA padding modes: PKCS#1 v1.5, RSA-OEAP and RSASVE.

Risk Assessment

In a TLS connection, an attacker who had observed a genuine connection could recover the pre-master secret and thus decrypt application data sent over that connection.

Recommendation

Update OpenSSL to a version containing the fix (3.0.8, 1.1.1t, 1.0.2zg or later) and consider disabling vulnerable RSA padding modes if possible.

Other vulnerabilities in OpenSSL

See all
Original NVD description (English source)

A timing based side channel exists in the OpenSSL RSA Decryption implementation which could be sufficient to recover a plaintext across a network in a Bleichenbacher style attack. To achieve a successful decryption an attacker would have to be able to send a very large number of trial messages for decryption. The vulnerability affects all RSA padding modes: PKCS#1 v1.5, RSA-OEAP and RSASVE. For example, in a TLS connection, RSA is commonly used by a client to send an encrypted pre-master secret to the server. An attacker that had observed a genuine connection between a client and a server could use this flaw to send trial messages to the server and record the time taken to process them. After a sufficiently large number of messages the attacker could recover the pre-master secret used for the original connection and thus be able to decrypt the application data sent over that connection.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS