Mozilla Network Security Services (NSS) before 3.16.2.1, 3.16.x before 3.16.5, and 3.17.x before 3.17.1, as used in Mozilla Firefox before 32.0.3, Mozilla Firefox ESR 24.x before 24.8.1 and 31.x before 31.1.1, Mozilla Thunderbird before 24.8.1 and 31.x before 31.1.2, Mozilla SeaMonkey before 2.29.1, Google Chrome before 37.0.2062.124 on Windows and OS X, and Google Chrome OS before 37.0.2062.120, does not properly parse ASN.1 values in X.509 certificates, which makes it easier for remote attackers to spoof RSA signatures via a crafted certificate, aka a "signature malleability" issue.

Use-after-free vulnerability in the CERT_DestroyCertificate function in libnss3.so in Mozilla Network Security Services (NSS) 3.x, as used in Firefox before 31.0, Firefox ESR 24.x before 24.7, and Thunderbird before 24.7, allows remote attackers to execute arbitrary code via vectors that trigger certain improper removal of an NSSCertificate structure from a trust domain.

The cert_TestHostName function in lib/certdb/certdb.c in the certificate-checking implementation in Mozilla Network Security Services (NSS) before 3.16 accepts a wildcard character that is embedded in an internationalized domain name's U-label, which might allow man-in-the-middle attackers to spoof SSL servers via a crafted certificate.

The ssl_Do1stHandshake function in sslsecur.c in libssl in Mozilla Network Security Services (NSS) before 3.15.4, when the TLS False Start feature is enabled, allows man-in-the-middle attackers to spoof SSL servers by using an arbitrary X.509 certificate during certain handshake traffic.