5 issues skipped by the security teams:
- CVE-2019-16910: Arm Mbed TLS before 2.19.0 and Arm Mbed Crypto before 2.0.0, when deterministic ECDSA is enabled, use an RNG with insufficient entropy for blinding, which might allow an attacker to recover a private key via side-channel attacks if a victim signs the same message many times. (For Mbed TLS, the fix is also available in versions 2.7.12 and 2.16.3.)
- CVE-2019-18222: The ECDSA signature implementation in ecdsa.c in Arm Mbed Crypto 2.1 and Mbed TLS through 2.19.1 does not reduce the blinded scalar before computing the inverse, which allows a local attacker to recover the private key via side-channel attacks.
- CVE-2020-10932: An issue was discovered in Arm Mbed TLS before 2.16.6 and 2.7.x before 2.7.15. An attacker that can get precise enough side-channel measurements can recover the long-term ECDSA private key by (1) reconstructing the projective coordinate of the result of scalar multiplication by exploiting side channels in the conversion to affine coordinates; (2) using an attack described by Naccache, Smart, and Stern in 2003 to recover a few bits of the ephemeral scalar from those projective coordinates via several measurements; and (3) using a lattice attack to get from there to the long-term ECDSA private key used for the signatures. Typically an attacker would have sufficient access when attacking an SGX enclave and controlling the untrusted OS.
- CVE-2020-10941: Arm Mbed TLS before 2.6.15 allows attackers to obtain sensitive information (an RSA private key) by measuring cache usage during an import.
- CVE-2020-16150: 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.
![[bug history graph]](https://qa.debian.org/data/bts/graphs/m/mbedtls.png){kind=link}