ArchLinux: 202101-7: mbedtls: private key recovery
Summary
A Lucky 13 timing side channel in mbedtls_ssl_decrypt_buf in library/ssl_msg.c in Trusted Firmware Mbed TLS through 2.23.0 allows an attacker to recover secret key information. This affects CBC mode because of a computed time difference based on a padding length. The issue is fixed in Mbed TLS 2.24.0, 2.16.8 and 2.7.17.
Resolution
Upgrade to 2.25.0-1.
# pacman -Syu "mbedtls>=2.25.0-1"
The problem has been fixed upstream in version 2.25.0.
References
https://bugs.archlinux.org/task/69128 https://security.archlinux.org/CVE-2020-16150
Workaround
None.