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.
aluigi.org/adv/qtsslame-adv.txt
aluigi.org/poc/qtsslame.zip
osvdb.org/65860
qt.gitorious.org/qt/qt/commit/c25c7c9bdfade6b906f37ac8bad44f6f0de57597
secunia.com/advisories/40389
secunia.com/advisories/46410
www.securityfocus.com/bid/41250
www.vupen.com/english/advisories/2010/1657
hermes.opensuse.org/messages/12056605