Rule History

SID: 2029554 • Source: et/open

Versions (3)

Version DetailsCurrent

Rev: 2 • Mar 2, 2020, 12:00 PM

Message:

ET USER_AGENTS Observed Suspicious UA (xa4)

Rule:

alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET USER_AGENTS Observed Suspicious UA (\xa4)"; flow:established,to_server; http.header; content:"|0d 0a|User-Agent|3a 20 a4 0d 0a|"; fast_pattern; http.user_agent; content:"|a4|"; bsize:1; classtype:bad-unknown; sid:2029554; rev:2; metadata:affected_product Any, attack_target Client_Endpoint, created_at 2020_03_02, deployment Perimeter, confidence High, signature_severity Minor, updated_at 2024_03_08;)

Created:

Mar 2, 2020, 12:00 PM

Updated:

Mar 8, 2024, 12:00 PM

DB Created:

Sep 21, 2024, 3:00 AM

DB Updated:

May 30, 2025, 12:04 AM

Filename:

rules/emerging-user_agents.rules