CommentCrew-threat-apt1 detects potential adversary behavior involving suspicious comment creation or modification in Azure resources, which may indicate reconnaissance or initial compromise activities. SOC teams should proactively hunt for this behavior to identify early-stage threat activity and prevent further lateral movement or data exfiltration.
YARA Rule
rule BOUNCER_APT1
{
meta:
author = "AlienVault Labs"
info = "CommentCrew-threat-apt1"
strings:
$s1 = "*Qd9kdgba33*%Wkda0Qd3kvn$*&><(*&%$E#%$#1234asdgKNAg@!gy565dtfbasdg" wide ascii
$s2 = "IDR_DATA%d" wide ascii
$s3 = "asdfqwe123cxz" wide ascii
$s4 = "Mode must be 0(encrypt) or 1(decrypt)." wide ascii
condition:
($s1 and $s2) or ($s3 and $s4)
}
This YARA rule can be deployed in the following contexts:
This rule contains 4 string patterns in its detection logic.
Scenario: Scheduled system maintenance job using PowerShell to clean temporary files
Filter/Exclusion: process.name != "powershell.exe" OR process.args NOT LIKE '%clean-temp-files%'
Scenario: Admin performing a routine log rotation using logrotate on Linux servers
Filter/Exclusion: process.name != "logrotate" OR process.args NOT LIKE '%/etc/logrotate.d/%'
Scenario: Database backup task using mysqldump to export data to a local directory
Filter/Exclusion: process.name != "mysqldump" OR process.args NOT LIKE '%--result-file=%'
Scenario: IT staff using rsync to synchronize files between servers during off-peak hours
Filter/Exclusion: process.name != "rsync" OR process.args NOT LIKE '%--exclude=/.*/%’
Scenario: User running a legitimate script via Task Scheduler to monitor system performance
Filter/Exclusion: process.name != "schtasks.exe" OR process.args NOT LIKE '/RU SYSTEM /XML "%systemroot%\Tasks\perfmon.xml%"'