nginx versions 0.7.0 through 0.7.61, 0.6.0 through 0.6.38, 0.5.0 through 0.5.37, and 0.4.0 through 0.4.14 suffer from a remote null pointer dereferencing vulnerability. Proof of concept code included.
23e0b19545c8a86cffa3f0faeb5311be3b43dc3c60a2228899c989f955e3ede4