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.
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.