CVE-2022-4304

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.

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