Vulnerability in OpenSSL
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.162 (96.8th percentile), scored .
Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 97th percentile — 96.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.162 · newest: 0.162 · change: 0.000
Affected products
- OpenSSL — versions 3.0.0, 1.1.1, 1.0.2
- Stormshield Endpoint Security
- Stormshield Sslvpn
- Stormshield Network Security
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.openssl.org/news/secadv/20230207.txt (vendor-advisory, Vendor Advisory)
- security.gentoo.org/glsa/202402-08
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2022-4304?
- CVE-2022-4304 is a medium-severity vulnerability in OpenSSL, classified under Observable Discrepancy. CVSS score: 5.9/10. Published 2023-02-08.
- How severe is CVE-2022-4304?
- Medium severity. CVSS v3 base score is 5.9 out of 10.
- Is CVE-2022-4304 known to be exploited?
- 18 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.