GNU Gnutls

A NULL pointer dereference flaw was found in GnuTLS. As Nettle's hash update functions internally call memcpy, providing zero-length input may cause undefined behavior. This flaw leads to a denial of service after authentication in rare circumstances.

It was found that the GnuTLS implementation of HMAC-SHA-384 was vulnerable to a Lucky thirteen style attack. Remote attackers could use this flaw to conduct distinguishing attacks and plain text recovery attacks via statistical analysis of timing data using crafted packets.

It was found that the GnuTLS implementation of HMAC-SHA-256 was vulnerable to a Lucky thirteen style attack. Remote attackers could use this flaw to conduct distinguishing attacks and plaintext-recovery attacks via statistical analysis of timing data using crafted packets.

The _gnutls_x509_verify_certificate function in lib/x509/verify.c in libgnutls in GnuTLS before 2.6.1 trusts certificate chains in which the last certificate is an arbitrary trusted, self-signed certificate, which allows man-in-the-middle attackers to insert a spoofed certificate for any Distinguished Name (DN).

GnuTLS incorrectly validates the first byte of padding in CBC modes

Gnutls: timing side-channel in the rsa-psk authentication

lib/x509/verify.c in GnuTLS before 3.1.22 and 3.2.x before 3.2.12 does not properly handle unspecified errors when verifying X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers via a crafted certificate.

lib/x509/verify.c in GnuTLS before 3.1.21 and 3.2.x before 3.2.11 treats version 1 X.509 certificates as intermediate CAs, which allows remote attackers to bypass intended restrictions by leveraging a X.509 V1 certificate from a trusted CA to issue new certificates.

GnuTLS before 2.7.6, when the GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT flag is not enabled, treats version 1 X.509 certificates as intermediate CAs, which allows remote attackers to bypass intended restrictions by leveraging a X.509 V1 certificate from a trusted CA to issue new certificates, a different vulnerability than CVE-2014-1959.

A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls handles verification of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run process on the same physical core as the victim process, could use this to extract plaintext or in some cases downgrade any TLS connections to a vulnerable server.

A cache-based side channel in GnuTLS implementation that leads to plain text recovery in cross-VM attack setting was found. An attacker could use a combination of "Just in Time" Prime+probe attack in combination with Lucky-13 attack to recover plain text using crafted packets.

Gnutls: vulnerability in gnutls sct extension parsing

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.

Double free vulnerability in GnuTLS before 3.3.17 and 3.4.x before 3.4.4 allows remote attackers to cause a denial of service via a long DistinguishedName (DN) entry in a certificate.

Multiple unspecified vulnerabilities in the DER decoder in GNU Libtasn1 before 3.6, as used in GnuTLS, allow remote attackers to cause a denial of service (out-of-bounds read) via crafted ASN.1 data.

Integer signedness error in the _gnutls_ciphertext2compressed function in lib/gnutls_cipher.c in libgnutls in GnuTLS before 2.2.4 allows remote attackers to cause a denial of service (buffer over-read and crash) via a certain integer value in the Random field in an encrypted Client Hello message within a TLS record with an invalid Record Length, which leads to an invalid cipher padding length, aka GNUTLS-SA-2008-1-3.

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.

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 (1) asn1_read_value_type and (2) asn1_read_value functions in GNU Libtasn1 before 3.6 allows context-dependent attackers to cause a denial of service (NULL pointer dereference and crash) via a NULL value in an ivalue argument.

The _gnutls_ciphertext2compressed function in lib/gnutls_cipher.c in GnuTLS 2.12.23 allows remote attackers to cause a denial of service (buffer over-read and crash) via a crafted padding length. NOTE: this might be due to an incorrect fix for CVE-2013-0169.

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.

verify.c in GnuTLS before 1.4.4, when using an RSA key with exponent 3, does not properly handle excess data in the digestAlgorithm.parameters field when generating a hash, which allows remote attackers to forge a PKCS #1 v1.5 signature that is signed by that RSA key and prevents GnuTLS from correctly verifying X.509 and other certificates that use PKCS, a variant of CVE-2006-4339.

The "record packet parsing" in GnuTLS 1.2 before 1.2.3 and 1.0 before 1.0.25 allows remote attackers to cause a denial of service, possibly related to padding bytes in gnutils_cipher.c.

Buffer overflow in the dane_query_tlsa function in the DANE library (libdane) in GnuTLS 3.1.x before 3.1.15 and 3.2.x before 3.2.5 allows remote servers to cause a denial of service (memory corruption) via a response with more than four DANE entries.

Off-by-one error in the dane_raw_tlsa in the DANE library (libdane) in GnuTLS 3.1.x before 3.1.16 and 3.2.x before 3.2.6 allows remote servers to cause a denial of service (memory corruption) via a response with more than four DANE entries. NOTE: this issue is due to an incomplete fix for CVE-2013-4466.

The _gnutls_x509_oid2mac_algorithm function in lib/gnutls_algorithms.c in GnuTLS before 1.4.2 allows remote attackers to cause a denial of service (crash) via a crafted X.509 certificate that uses a hash algorithm that is not supported by GnuTLS, which triggers a NULL pointer dereference.

gnutls-cli in GnuTLS before 2.6.6 does not verify the activation and expiration times of X.509 certificates, which allows remote attackers to successfully present a certificate that is (1) not yet valid or (2) no longer valid, related to lack of time checks in the _gnutls_x509_verify_certificate function in lib/x509/verify.c in libgnutls_x509, as used by (a) Exim, (b) OpenLDAP, and (c) libsoup.

GnuTLS before 3.1.0 does not verify that the RSA PKCS #1 signature algorithm matches the signature algorithm in the certificate, which allows remote attackers to conduct downgrade attacks via unspecified vectors.

lib/pk-libgcrypt.c in libgnutls in GnuTLS before 2.6.6 does not properly handle invalid DSA signatures, which allows remote attackers to cause a denial of service (application crash) and possibly have unspecified other impact via a malformed DSA key that triggers a (1) free of an uninitialized pointer or (2) double free.

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 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.

GnuTLS before 2.9.10 does not verify the activation and expiration dates of CA certificates, which allows man-in-the-middle attackers to spoof servers via a certificate issued by a CA certificate that is (1) not yet valid or (2) no longer valid.

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.

Gnutls: gnutls: security bypass allows acceptance of revoked server certificates via crafted ocsp response