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HackTool:Win32/Badcastle.A!dha
Aliases: No associated aliases
Summary
HackTool:Win32/Badcastle.A!dha is a weaponized utility designed for privilege escalation on Windows. Unlike self-propagating malware, this tool requires a threat actor to already have a foothold on the device, through a low-privileged user account. Its core purpose is to breach the boundary between standard user rights and powerful administrative privileges.
The tool operates by exploiting specific weaknesses in the Windows NetNTLM authentication process. Its techniques a technique known as an NTLM relay attack, manipulating legitimate Windows functions to impersonate a higher-privileged user who is interactively logged on. This process allows the threat actor to steal and reuse authentication tokens, granting them system-level access without knowing the user's password.
In a cyberattack chain, HackTool:Win32/Badcastle.A!dha serves a critical post-compromise function. By elevating their access, threat actors can deactivate security software, deploy additional payloads like ransomware or backdoors, and move laterally across a network. Its deployment signifies a threat actor’s intent to transition from initial access to full-scale control of the environment.
The "!dha" suffix in the detection name indicates that this is a heuristic or behavioral detection. This means that the identification occurs by analyzing suspicious actions and patterns of code that are like known backdoor behaviors as opposed to having a unique, identified fingerprint. Heuristic detection is used for new variants of known malware families or for detecting threats that exhibit polymorphism that modify the code that is visible on the surface, making it hard to detect.
- Disconnect the compromised device from all networks (both wired and Wi-Fi) as soon as possible. This severs the threat actor’s remote connection and prevents further data exfiltration.
- Check directories like C:\ProgramData for the Badcastle’s binaries and any related files and delete them.
- Investigate security logs to determine the initial attack vector. If the device remains unstable or re-infected, restore it from a known-clean backup.
- Inspect local user accounts and group memberships. Remove any unauthorized accounts, such as those added to the Administrators group, and reset passwords for possible compromised built-in accounts like 'Guest'.
Microsoft Defender Antivirus automatically removes threats as they are detected. However, many infections can leave remnant files and system changes. Updating your antimalware definitions and running a full scan might help address these remnant artifacts.
You can also visit our advanced troubleshooting page or search the Microsoft virus and malware community for more help.
