Use of a Broken or Risky Cryptographic Algorithm in the function mbedtls_mpi_exp_mod() in lignum.c in Mbed TLS Mbed TLS all versions before 3.0.0 2.27.0 or 2.16.11 allows attackers with access to precise enough timing and memory access information (typically an untrusted operating system attacking a secure enclave such as SGX or the TrustZone secure world) to recover the private keys used in RSA.

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MatrixSSL pstm_exptmod Function Miscalculation Vulnerability

INSIDE Secure MatrixSSL is an embedded, open source SSLv3 stack from INSIDE Secure, France, designed for small applications and devices. The pstmexptmod in MatrixSSL inputs incorrect results for certain parameters, causing the associated cryptographic functions to fail to handle the private key...