alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET EXPLOIT VNC Server Not Requiring Authentication"; flow:established,to_client; flowbits:isset,BSis.vnc.setup; flowbits:set,BSvnc.auth.offered; flowbits:unset,BSis.vnc.setup; content:"|01 01|"; depth:2; reference:url,www.realvnc.com/docs/rfbproto.pdf; reference:cve,2006-2369; classtype:misc-activity; sid:2002924; rev:8; metadata:created_at 2010_07_30, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2026_07_14;)