Matrix SSL 4.x through 4.6.0 and Rambus TLS Toolkit have a length-subtraction integer overflow for Client Hello Pre-Shared Key extension parsing in the TLS 1.3 server. An attacked device calculates an SHA-2 hash over at least 65 KB (in RAM). With a large number of crafted TLS messages, the CPU becomes heavily loaded. This occurs in tls13VerifyBinder and tls13TranscriptHashUpdate.

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.

MatrixSSL 4.0.4 through 4.5.1 has an integer overflow in matrixSslDecodeTls13. A remote attacker might be able to send a crafted TLS Message to cause a buffer overflow and achieve remote code execution. This is fixed in 4.6.0.

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.