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.
2023-02-08T20:15:23.887
2025-03-20T21:15:14.890
Modified
CVSSv3.1: 5.9 (MEDIUM)
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Application | openssl | openssl | < 1.0.2zg | Yes |
| Application | openssl | openssl | < 1.1.1t | Yes |
| Application | openssl | openssl | < 3.0.8 | Yes |
| Application | stormshield | endpoint_security | < 7.2.40 | Yes |
| Application | stormshield | sslvpn | < 3.2.1 | Yes |
| Application | stormshield | stormshield_network_security | < 2.7.11 | Yes |
| Application | stormshield | stormshield_network_security | < 3.7.34 | Yes |
| Application | stormshield | stormshield_network_security | < 3.11.22 | Yes |
| Application | stormshield | stormshield_network_security | < 4.3.16 | Yes |
| Application | stormshield | stormshield_network_security | < 4.6.3 | Yes |