CVE-2022-46392: 
Mbed TLS vulnerability analysis and mitigation

CVE-2022-46392 affects Mbed TLS versions before 2.28.2 and 3.x before 3.3.0. The vulnerability was discovered in December 2022 and involves a side-channel attack against RSA private key operations. The affected software, Mbed TLS, is a lightweight open-source cryptographic and SSL/TLS library written in C, commonly used in embedded applications (NVD, Mbed Release).

The vulnerability occurs when the window size (MBEDTLS_MPI_WINDOW_SIZE) used for RSA exponentiation is 3 or smaller. The issue was discovered by researchers Zili KOU, Wenjian HE, Sharad Sinha, and Wei ZHANG, and was detailed in their paper 'Cache Side-channel Attacks and Defenses of the Sliding Window Algorithm in TEEs' presented at Design, Automation and Test in Europe 2023. The vulnerability has been assigned a CVSS v3.1 Base Score of 5.3 (Medium) with vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N (NVD).

An adversary with access to precise enough information about memory accesses can recover an RSA private key after observing the victim performing a single private-key operation. This typically occurs in scenarios where an untrusted operating system is attacking a secure enclave (NVD).

The vulnerability has been fixed in Mbed TLS versions 2.28.2 and 3.3.0. Users are recommended to upgrade to these or later versions. Fedora has released security updates for both Fedora 36 and 37 to address this vulnerability (Fedora 36, Fedora 37).