Forensic tools reconstruct attacker screen activity from thousands of 64x64 pixel bitmap fragments stored in RDP cache files, revealing viewed files and commands. Investigators identify RDP attackers through Windows Event IDs 4624/4625 and unique Network Level Authentication patterns that reveal connection attempts and successful breaches. Cybersecurity researchers have developed innovative forensic methods to track sophisticated attackers who exploit Remote Desktop Protocol (RDP) for lateral movement within enterprise networks. Clipboard data, process artifacts, and registry entries expose passwords, connection history, and lateral movement targets that attackers cannot easily delete. The technique proved particularly effective in a ransomware investigation where bitmap cache analysis revealed the attacker’s login to a cloud storage service, exposing additional victim data stored in their account. This breakthrough technique transforms what attackers believe to be stealthy operations into detailed digital footprints, providing incident responders with unprecedented visibility into malicious activities across compromised systems. These cache files contain thousands of 64×64 pixel tiles representing portions of the remote screen that attackers viewed during their sessions. Advanced techniques can decrypt RDP traffic when session keys are recovered from memory dumps, potentially enabling complete session replay using tools like RDP-Replay. Memory-extracted session keys enable RDP traffic decryption and complete session replay using tools like RDP-Replay to visualize attacker actions. Security experts demonstrate how every click, keystroke, and screen interaction during remote sessions generates recoverable artifacts that paint a complete picture of unauthorized access. The unique Logon ID field links various activities to specific sessions, enabling investigators to trace all actions performed during a particular intrusion. Registry analysis uncovers connection history in HKCU\Software\Microsoft\Terminal Server Client\Servers, providing evidence of lateral movement targets. One case revealed an attacker’s activities by reconstructing fragments showing a PowerShell session with credential dumping tools. The Network Level Authentication (NLA) creates unique patterns where RDP connections initially appear as Logon Type 3 (Network) before transitioning to Type 10 (RemoteInteractive). This creates a timeline of connection attempts that helps investigators map brute-force activities and successful breaches. “We’ve successfully recovered file names, application windows, and even command prompt output from bitmap caches,” researchers report.
This Cyber News was published on cybersecuritynews.com. Publication date: Mon, 14 Jul 2025 13:40:31 +0000