alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Possible UPSTYLE Command Attempt"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"img|5b|"; fast_pattern; pcre:"/img\x5b[a-zA-Z0-9+/=]{10,}\x5d/U"; content:!"|0d 0a|Referer|0d 0a|"; reference:url,www.volexity.com/blog/2024/04/12/zero-day-exploitation-of-unauthenticated-remote-code-execution-vulnerability-in-globalprotect-cve-2024-3400/; reference:url,unit42.paloaltonetworks.com/cve-2024-3400/; classtype:trojan-activity; sid:2052026; rev:1; metadata:affected_product Palo_Alto_Networks, attack_target Networking_Equipment, tls_state TLSDecrypt, created_at 2024_04_12, cve CVE_2024_3400, deployment Perimeter, deployment SSLDecrypt, malware_family UPSTYLE, performance_impact Moderate, confidence Low, signature_severity Major, updated_at 2024_04_12; target:dest_ip;)