ThreatFox: Vidar IOCs | SOC Hunt Feed

Hunt Hypothesis

This hunt targets the presence of Vidar malware indicators, a remote access trojan frequently used by threat actors to establish persistent footholds and exfiltrate sensitive data. Proactively hunting for these IOCs in Azure Sentinel allows the SOC to identify compromised endpoints early, mitigating the risk of lateral movement and data theft before the adversary can fully establish control.

IOC Summary

Malware Family: Vidar Total IOCs: 3 IOC Types: sha256_hash

Type	Value	Threat Type	First Seen	Confidence
sha256_hash	`4ff5fe4e66d8f65cdfc2a3b16720cdbd3f7908fc7d861b8810293703aa61c0be`	payload	2026-09-27	95%
sha256_hash	`6cc550f8e136e736ea7222dc3e0ea410b31815a65ce7ba1f42230c1ccbd13b17`	payload	2026-09-27	95%
sha256_hash	`0017821181723261801e24abb9d33c739f382889d46dbf46d320c87ac62e5ca6`	payload	2026-09-27	95%

KQL: Hash Hunt

// Hunt for files matching known malicious hashes
// Source: ThreatFox - Vidar
let malicious_hashes = dynamic(["4ff5fe4e66d8f65cdfc2a3b16720cdbd3f7908fc7d861b8810293703aa61c0be", "6cc550f8e136e736ea7222dc3e0ea410b31815a65ce7ba1f42230c1ccbd13b17", "0017821181723261801e24abb9d33c739f382889d46dbf46d320c87ac62e5ca6"]);
DeviceFileEvents
| where SHA256 in (malicious_hashes) or SHA1 in (malicious_hashes) or MD5 in (malicious_hashes)
| project Timestamp, DeviceName, FileName, FolderPath, SHA256, InitiatingProcessFileName
| order by Timestamp desc

Required Data Sources

Sentinel Table	Notes
`DeviceFileEvents`	Ensure this data connector is enabled

References

ThreatFox — Vidar

False Positive Guidance

Legacy Application Deployment via Group Policy: A standard enterprise deployment of a legacy Java-based application (e.g., an internal ERP client) uses a JAR file that shares the same SHA-256 hash or file path structure as one of the Vidar IOCs due to outdated build practices. To mitigate this, add an exclusion for the specific C:\Program Files\LegacyApp\bin\ directory or filter by the parent process gpupdate.exe if the IOC is triggered during policy refresh.
Third-Party Vendor Support Tool: A vendor’s remote support utility (e.g., TeamViewer or LogMeIn) installs a helper executable in C:\Users\<ServiceAccount>\AppData\Local\Temp\ that matches the Vidar IOCs’ file name or hash because the vendor uses a generic naming convention like helper.exe or update.exe. Exclude this by filtering for the specific vendor’s installation path (e.g., C:\Program Files (x86)\VendorName\) or by correlating the event with a known vendor service account.
Scheduled Maintenance Job for Database Backups: A scheduled task (schtasks) runs a backup script that writes a temporary archive file to C:\Temp\ or C:\Windows\Temp\ with a name that collides with a Vidar IOC (e.g., backup.zip or temp.dat). If the IOC is based on file name or hash, exclude events where the parent process is svchost.exe (specifically the Schedule service) or filter by the specific scheduled task name (e.g., DailyDBBackup).
Development Environment Testing: A developer on a jump host or dev box runs a test build of a new application component that is intentionally named to match a Vidar IOC for testing purposes (e.g., vidar_test.exe or a specific hash). Exclude