wolfSSL CyaSSL before 2.9.4 does not properly validate X.509 certificates with unknown critical extensions, which allows man-in-the-middle attackers to spoof servers via crafted X.509 certificate.

wolfSSL CyaSSL before 2.9.4 allows remote attackers to cause a denial of service (NULL pointer dereference) via (1) a request for the peer certificate when a certificate parsing failure occurs or (2) a client_key_exchange message when the ephemeral key is not found.

The TLS and DTLS implementations in wolfSSL CyaSSL before 2.5.0 do not properly consider timing side-channel attacks on a noncompliant MAC check operation during the processing of malformed CBC padding, which allows remote attackers to conduct distinguishing attacks and plaintext-recovery attacks via statistical analysis of timing data for crafted packets, a related issue to CVE-2013-0169.

yaSSL CyaSSL before 2.0.8 allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via a crafted X.509 certificate.