Updated: 2024-02-04 20:06:28.289573
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.
| Links | NIST | CIRCL | RHEL | Ubuntu |
| Severity | Score | |
|---|---|---|
| CVSS Version 2.x | 0 | |
| CVSS Version 3.x | MEDIUM | 5.9 |
| OS name | Project name | Version | Score | Severity | Status | Errata | Last updated |
|---|---|---|---|---|---|---|---|
| AlmaLinux 9.2 ESU | openssl | 3.0.7 | 5.9 | MEDIUM | Ignored | 2023-11-08 04:07:54 | |
| AlmaLinux 9.2 FIPS | openssl | 3.0.7 | 5.9 | MEDIUM | Ignored | 2023-11-21 04:12:28 | |
| CentOS 7 ELS | openssl | 1.0.2k | 5.9 | MEDIUM | In Testing | 2024-07-19 12:12:26 | |
| CentOS 8.4 ELS | openssl | 1.1.1g | 5.9 | MEDIUM | Released | CLSA-2023:1680206329 | 2023-03-30 17:04:32 |
| CentOS 8.5 ELS | openssl | 1.1.1k | 5.9 | MEDIUM | Released | CLSA-2023:1680210075 | 2023-03-30 17:04:31 |
| Ubuntu 16.04 ELS | openssl | 1.0.2g-1 | 5.9 | MEDIUM | Ignored | 2023-10-26 11:09:36 | |
| Ubuntu 18.04 ELS | openssl | 1.1.1-1 | 5.9 | MEDIUM | Already Fixed | 2023-11-06 08:36:22 |