RSA implementation bug in AVX512IFMA instructions

Vulnerability

Overview CVE-2022-2274 is a high-severity vulnerability in OpenSSL 3.0.4 introduced in the RSA implementation for x86_64 CPUs that support AVX512IFMA instructions. A bug in the assembly-optimized code causes incorrect computation when processing 2048-bit RSA private keys, leading to heap memory corruption [1][3]. The issue was first reported to OpenSSL on 22 June 2022 by Xi Ruoyao, who also developed the fix [3].

Exploitation and

Attack Surface The vulnerability specifically affects SSL/TLS servers and other services using 2048-bit RSA private keys on hardware with AVX512IFMA support. Memory corruption occurs during the RSA private key operation itself, meaning an attacker able to trigger such an operation on a vulnerable server (for example, by initiating a TLS handshake requiring RSA decryption) could potentially trigger the corruption [1][3]. The advisory notes that proper testing of OpenSSL on vulnerable machines would fail, which could be detected before deployment [3].

Impact

Successful exploitation could allow an attacker to cause a heap-based buffer overflow, as confirmed by AddressSanitizer findings showing a read of size 8 beyond an allocated 128-byte region [2]. This memory corruption is described as potentially leading to remote code execution on the machine performing the computation [1][3]. No other attack vectors (e.g., man-in-the-middle) are mentioned in the sources.

Mitigation

The vulnerability is confined to OpenSSL version 3.0.4; OpenSSL 1.1.1 and 1.0.2 are not affected [3]. Users of OpenSSL 3.0.4 on affected hardware must upgrade to OpenSSL 3.0.5, released on 5 July 2022 [3][4]. The Rust crate openssl-src has also been patched (version >=300.0.9) [4]. No workaround other than upgrading is provided.