CVE-2022-4304

medium

Description

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.

References

https://www.openssl.org/news/secadv/20230207.txt

https://security.gentoo.org/glsa/202402-08

Details

Source: Mitre, NVD

Published: 2023-02-08

Risk Information

CVSS v2

Base Score: 5.4

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 5.9

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

Severity: Medium