The _gnutls_ecc_ansi_x963_export function in gnutls_ecc.c in GnuTLS 3.x before 3.1.28, 3.2.x before 3.2.20, and 3.3.x before 3.3.10 allows remote attackers to cause a denial of service (out-of-bounds write) via a crafted (1) Elliptic Curve Cryptography (ECC) certificate or (2) certificate signing requests (CSR), related to generating key IDs.

The gnutls_x509_dn_oid_name function in lib/x509/common.c in GnuTLS 3.0 before 3.1.20 and 3.2.x before 3.2.10 allows remote attackers to cause a denial of service (NULL pointer dereference) via a crafted X.509 certificate, related to a missing LDAP description for an OID when printing the DN.

The TLS implementation in GnuTLS before 2.12.23, 3.0.x before 3.0.28, and 3.1.x before 3.1.7 does 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.

The asn1_get_length_der function in decoding.c in GNU Libtasn1 before 2.12, as used in GnuTLS before 3.0.16 and other products, does not properly handle certain large length values, which allows remote attackers to cause a denial of service (heap memory corruption and application crash) or possibly have unspecified other impact via a crafted ASN.1 structure.

gnutls_cipher.c in libgnutls in GnuTLS before 2.12.17 and 3.x before 3.0.15 does not properly handle data encrypted with a block cipher, which allows remote attackers to cause a denial of service (heap memory corruption and application crash) via a crafted record, as demonstrated by a crafted GenericBlockCipher structure.

Double free vulnerability in libgnutls in GnuTLS before 3.0.14 allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a crafted certificate list.

The DTLS implementation in GnuTLS 3.0.10 and earlier executes certain error-handling code only if there is a specific relationship between a padding length and the ciphertext size, which makes it easier for remote attackers to recover partial plaintext via a timing side-channel attack, a related issue to CVE-2011-4108.

Buffer overflow in the gnutls_session_get_data function in lib/gnutls_session.c in GnuTLS 2.12.x before 2.12.14 and 3.x before 3.0.7, when used on a client that performs nonstandard session resumption, allows remote TLS servers to cause a denial of service (application crash) via a large SessionTicket.

The Network Security Services (NSS) library before 3.12.3, as used in Firefox; GnuTLS before 2.6.4 and 2.7.4; OpenSSL 0.9.8 through 0.9.8k; and other products support MD2 with X.509 certificates, which might allow remote attackers to spoof certificates by using MD2 design flaws to generate a hash collision in less than brute-force time. NOTE: the scope of this issue is currently limited because the amount of computation required is still large.