rule M_Hunting_Backdoor_ZIPLINE_1 {
  meta:
    author = "Mandiant"
    description = "This rule detects unique strings in ZIPLINE, a passive ELF backdoor that waits for incoming TCP connections to receive commands from the threat actor."
    reference = "https://www.mandiant.com/resources/blog/suspected-apt-targets-ivanti-zero-day"
    date = "2024-01-11"
    score = 75
    id = "753884d6-d4c1-5e94-9d2c-f6ebb7bfaf85"
  strings:
    $s1 = "SSH-2.0-OpenSSH_0.3xx" ascii
    $s2 = "$(exec $installer $@)" ascii
    $t1 = "./installer/do-install" ascii
    $t2 = "./installer/bom_files/" ascii
    $t3 = "/tmp/data/root/etc/ld.so.preload" ascii
    $t4 = "/tmp/data/root/home/etc/manifest/exclusion_list" ascii
  condition:
    uint32(0) == 0x464c457f and
    filesize < 5MB and
    ((1 of ($s*)) or
    (3 of ($t*)))
}