The HTTP Inspect preprocessor (http_inspect) in Snort 2.4.0 through 2.4.4 allows remote attackers to bypass "uricontent" rules via a carriage return (\r) after the URL and before the HTTP declaration.

The frag3 preprocessor in Sourcefire Snort 2.4.3 does not properly reassemble certain fragmented packets with IP options, which allows remote attackers to evade detection of certain attacks, possibly related to IP option lengths.

Stack-based buffer overflow in the Back Orifice (BO) preprocessor for Snort before 2.4.3 allows remote attackers to execute arbitrary code via a crafted UDP packet.