An issue in MatrixSSL 4.5.1-open and earlier leads to failure to securely check the SessionID field, resulting in the misuse of an all-zero MasterSecret that can decrypt secret data.

In MatrixSSL before 4.2.2 Open, the DTLS server can encounter an invalid pointer free (leading to memory corruption and a daemon crash) via a crafted incoming network message, a different vulnerability than CVE-2019-14431.

MatrixSSL 4.2.1 and earlier contains a timing side channel in ECDSA signature generation. This allows a local or a remote attacker, able to measure the duration of hundreds to thousands of signing operations, to compute the private key used. The issue occurs because crypto/pubkey/ecc_math.c scalar multiplication leaks the bit length of the scalar.

In MatrixSSL 3.8.3 Open through 4.2.1 Open, the DTLS server mishandles incoming network messages leading to a heap-based buffer overflow of up to 256 bytes and possible Remote Code Execution in parseSSLHandshake in sslDecode.c. During processing of a crafted packet, the server mishandles the fragment length value provided in the DTLS message.

MatrixSSL before 4.2.1 has an out-of-bounds read during ASN.1 handling.

pubRsaDecryptSignedElementExt in MatrixSSL 4.0.1 Open, as used in Inside Secure TLS Toolkit, has a stack-based buffer overflow during X.509 certificate verification because of missing validation in psRsaDecryptPubExt in crypto/pubkey/rsa_pub.c.

MatrixSSL through 3.9.5 Open allows a memory-cache side-channel attack on ECDSA signatures, aka the Return Of the Hidden Number Problem or ROHNP. To discover an ECDSA key, the attacker needs access to either the local machine or a different virtual machine on the same physical host.