Versions (3)
Version DetailsCurrent
Rev: 1 • Apr 19, 2024, 12:00 PMET MALWARE Suspected Kapeka/ICYWELL Backdoor Server Response (upgrade backdoor)
alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Suspected Kapeka/ICYWELL Backdoor Server Response (upgrade backdoor)"; flow:established,to_client; file.data; content:"|3a 20 22|Upgrade backdoor|22|,"; fast_pattern; content:"backdoor|3a|"; distance:0; reference:url,labs.withsecure.com/content/dam/labs/docs/WithSecure-Research-Kapeka.pdf; reference:url,services.google.com/fh/files/misc/apt44-unearthing-sandworm.pdf; classtype:trojan-activity; sid:2052179; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, affected_product Windows_11, attack_target Client_Endpoint, tls_state TLSDecrypt, created_at 2024_04_19, deployment Perimeter, deployment SSLDecrypt, malware_family SANDWORM, malware_family APT44, confidence Medium, signature_severity Major, tag RAT, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_19; target:dest_ip;)
Apr 19, 2024, 12:00 PM
Apr 19, 2024, 12:00 PM
Apr 19, 2024, 10:00 PM
Aug 11, 2025, 10:35 PM
rules/emerging-malware.rules