CyaSSL does not check the key usage extension in leaf certificates, which allows remote attackers to spoof servers via a crafted server certificate not authorized for use in an SSL/TLS handshake.

A specially crafted x509 certificate can cause a single out of bounds byte overwrite in wolfSSL through 3.10.2 resulting in potential certificate validation vulnerabilities, denial of service and possible remote code execution. In order to trigger this vulnerability, the attacker needs to supply a malicious x509 certificate to either a server or a client application using this library.

wolfSSL before 3.10.2 has an out-of-bounds memory access with loading crafted DH parameters, aka a buffer overflow triggered by a malformed temporary DH file.

wolfSSL before 3.11.0 does not prevent wc_DhAgree from accepting a malformed DH key.

In versions of wolfSSL before 3.10.2 the function fp_mul_comba makes it easier to extract RSA key information for a malicious user who has access to view cache on a machine.

The C software implementation of AES Encryption and Decryption in wolfSSL (formerly CyaSSL) before 3.9.10 makes it easier for local users to discover AES keys by leveraging cache-bank timing differences.

The C software implementation of ECC in wolfSSL (formerly CyaSSL) before 3.9.10 makes it easier for local users to discover RSA keys by leveraging cache-bank hit differences.

The C software implementation of RSA in wolfSSL (formerly CyaSSL) before 3.9.10 makes it easier for local users to discover RSA keys by leveraging cache-bank hit differences.

wolfSSL (formerly CyaSSL) before 3.6.8 allows remote attackers to cause a denial of service (resource consumption or traffic amplification) via a crafted DTLS cookie in a ClientHello message.

wolfSSL (formerly CyaSSL) before 3.6.8 does not properly handle faults associated with the Chinese Remainder Theorem (CRT) process when allowing ephemeral key exchange without low memory optimizations on a server, which makes it easier for remote attackers to obtain private RSA keys by capturing TLS handshakes, aka a Lenstra attack.