Rewterz Threat Alert – Dark Crystal RAT – Active IOCs

Severity

High

Analysis Summary

Researchers have analyzed the Dark Crystal RAT capabilities and C2 message format. Unlike a real RAT server, this one does not have a user interface to allow the attacker to pick and launch commands. Instead, it has a pre-scripted command list that it sends to the RAT. When the server starts up, it uses the Python BaseHTTPServer to begin listening for incoming web requests. Incoming POST requests are assumed to hold a file that the RAT is uploading to the server; this server assumes all file uploads are screenshots and saves them to “screen.png”. The server sends four types of commands in sequence: first, it hides the desktop icons; then, it causes the string “Hello this is tech support” to be spoken; next, it displays a message box asking for a password; finally, it launches the Windows Calculator.

Impact

• Data Theft
• Exposure of Sensitive Data

Indicators of Compromise

MD5

• a3d1b172ab3266a6a63e7416ed637dee
• d1263457a84d46fc589b980eae2b1918

SHA-256

• 01d524096aa4f6ee863d424b36ee237a93bdd66466dca5ef0efc4effc2bed661
• 8acc1526714f82e0444141ddf87a7f6d83b3d6e3ebb46397f324695b9e19da81
• f2f7b95883759bcef4193f3ddd38a44c16ce38f2234cac319abf2302f2c5dd3d
• 06ceb23744199b0867e20669cffc40165a85c2d10f3a7fbd4855466cd260b5a8

SHA-1

• 9bfaecc69a820a2c3ca51a864ac7e7799def0f16
• 93a8f48af0622ee54e2a0614d0f61a7483b3ee9f

Remediation

Upgrade your firmware to the latest version of TL-WR840N(EU)_V5_211109 from vendor website here:https://www.tp-link.com/us/press/security-advisory/