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Trojan:VBS/Sibot.B!dha
Aliases: No associated aliases
Summary
This threat is a malware implemented in VBScript designed to persist on the infected machine then download and launch a payload from a remote command-and-control (C2) server. The malware author names the VBScript file with a name that impersonates legitimate Windows tasks and is either stored in the registry of the compromised system or in an obfuscated format on disk. The VBScript then runs via a scheduled task.
Microsoft Defender Antivirus detects and blocks this threat. It will quarantine the malware even if the process is running.
For more information and guidance from Microsoft, read the following:
Microsoft Defender Antivirus automatically removes threats as they are detected. If you have cloud-delivered protection, your device gets the latest defenses against new and unknown threats. If you don't have this feature enabled, update your antimalware definitions and run a full scan to remove this threat.
To help reduce the impact of this threat, you can:
- Immediately isolate the affected device. If malicious code has been launched, it is likely that the device is under complete attacker control.
- Identify the accounts that have been used on the affected device and consider these accounts compromised. Reset passwords or decommission the accounts.
- Investigate how the affected endpoint might have been compromised. Check web and email traffic to determine how the malware arrived.
- Investigate the device timeline for indications of lateral movement activities using one of the compromised accounts. Check for additional tools that attackers might have dropped to enable credential access, lateral movement, and other attack activities.
You can also visit our advanced troubleshooting page or search the Microsoft community for more help.
