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Bug #5929

Updated by Victor Julien over 1 year ago

Consider the following rules and the attached pcap 
 <pre> <code> 
 alert http $HOME_NET any -> $EXTERNAL_NET any (flow:established,to_server; urilen:<70; http.uri; content:".php?"; content:"=01&"; distance:4; within:4; fast_pattern; sid:1;) 
 alert http $HOME_NET any -> $EXTERNAL_NET any (flow:established,to_server; http.uri; bsize:<70; content:".php?"; content:"=01&"; distance:4; within:4; fast_pattern; sid:2;) 
 alert http $HOME_NET any -> $EXTERNAL_NET any (flow:established,to_server; urilen:<70; http.uri; content:".php?"; content:"=01&"; distance:4; within:4; sid:3;) 
 alert http $HOME_NET any -> $EXTERNAL_NET any (flow:established,to_server; http.uri; content:".php?"; content:"=01&"; distance:4; within:4; fast_pattern; sid:4;) 
 </pre> </code> 

 Only sid:2, sid:3 and sid:4 fire on git-master (Suricata 7.0.0-rc2-dev (416a780f6 2023-03-17)) and 6.0.10. 

 sid:2 is a good workaround, however, it lacks whatever optimization that urilen has to make it effect checks (see https://redmine.openinfosecfoundation.org/issues/4226#note-3) 

 see https://redmine.openinfosecfoundation.org/issues/5197 for a simliar issue

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