src/http/ngx_http_parse.c in nginx (aka Engine X) 0.1.0 through 0.4.14, 0.5.x before 0.5.38, 0.6.x before 0.6.39, 0.7.x before 0.7.62, and 0.8.x before 0.8.14 allows remote attackers to cause a denial of service (NULL pointer dereference and worker process crash) via a long URI.
https://www.redhat.com/archives/fedora-package-announce/2009-December/msg00449.html
https://www.redhat.com/archives/fedora-package-announce/2009-December/msg00442.html
https://www.redhat.com/archives/fedora-package-announce/2009-December/msg00428.html
https://bugzilla.redhat.com/show_bug.cgi?id=539565
http://www.openwall.com/lists/oss-security/2009/11/23/10
http://www.openwall.com/lists/oss-security/2009/11/20/6
http://www.openwall.com/lists/oss-security/2009/11/20/1
http://www.debian.org/security/2009/dsa-1920
http://sysoev.ru/nginx/patch.null.pointer.txt
http://security.gentoo.org/glsa/glsa-201203-22.xml
http://security.debian.org/pool/updates/main/n/nginx/nginx_0.4.13-2+etch3.diff.gz