QSslSocket in Qt before 4.7.0-rc1 recognizes a wildcard IP address in the subject's Common Name field of an X.509 certificate, which might allow man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority.

Heap-based buffer overflow in the Lookup_MarkMarkPos function in the HarfBuzz module (harfbuzz-gpos.c), as used by Qt before 4.7.4 and Pango, allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a crafted font file.

The QSslSocketBackendPrivate::transmit function in src_network_ssl_qsslsocket_openssl.cpp in Qt 4.6.3 and earlier allows remote attackers to cause a denial of service (infinite loop) via a malformed request.

src/network/ssl/qsslcertificate.cpp in Nokia Trolltech Qt 4.x does not properly handle a '\0' character in a domain name in the Subject Alternative Name 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, a related issue to CVE-2009-2408.

The UTF-8 decoder in codecs/qutfcodec.cpp in Qt 3.3.8 and 4.2.3 does not reject long UTF-8 sequences as required by the standard, which allows remote attackers to conduct cross-site scripting (XSS) and directory traversal attacks via long sequences that decode to dangerous metacharacters.