Multiple use-after-free vulnerabilities in libxml2 2.5.10, 2.6.16, 2.6.26, 2.6.27, and 2.6.32, and libxml 1.8.17, allow context-dependent attackers to cause a denial of service (application crash) via crafted (1) Notation or (2) Enumeration attribute types in an XML file, as demonstrated by the Codenomicon XML fuzzing framework.

Mozilla Network Security Services (NSS) before 3.12.3, Firefox before 3.0.13, Thunderbird before 2.0.0.23, and SeaMonkey before 1.1.18 do not properly handle a '\0' character in a domain name in the subject's Common Name (CN) field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority. NOTE: this was originally reported for Firefox before 3.5.

The ippReadIO function in cups/ipp.c in cupsd in CUPS before 1.3.10 does not properly initialize memory for IPP request packets, which allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a scheduler request with two consecutive IPP_TAG_UNSUPPORTED tags.

The PNG reference library (aka libpng) before 1.0.43, and 1.2.x before 1.2.35, as used in pngcrush and other applications, allows context-dependent attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted PNG file that triggers a free of an uninitialized pointer in (1) the png_read_png function, (2) pCAL chunk handling, or (3) setup of 16-bit gamma tables.

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).