ThreatFox: Venus Stealer IOCs

Hunt Hypothesis

This detection identifies active communication between Azure Sentinel endpoints and known indicators of compromise linked to the Venus Stealer malware, which targets sensitive credentials and system data. Proactively hunting for these specific IOCs is critical because Venus Stealer’s ability to exfiltrate stored passwords and browser tokens can lead to rapid lateral movement and significant data loss if not immediately contained.

IOC Summary

Malware Family: Venus Stealer Total IOCs: 3 IOC Types: sha256_hash, sha1_hash, md5_hash

Type	Value	Threat Type	First Seen	Confidence
sha1_hash	`bcf32c802a7a27b2bfe6ea5e26b75091c8a76175`	payload	2026-08-28	95%
md5_hash	`4878d995e4e23c6961c91179e6e2c704`	payload	2026-08-28	95%
sha256_hash	`5cb54c53e2169a23a815d87229b00c63d1d3c8c0d19e0f92b5e83bd231481419`	payload	2026-08-28	95%

KQL: Hash Hunt

// Hunt for files matching known malicious hashes
// Source: ThreatFox - Venus Stealer
let malicious_hashes = dynamic(["bcf32c802a7a27b2bfe6ea5e26b75091c8a76175", "4878d995e4e23c6961c91179e6e2c704", "5cb54c53e2169a23a815d87229b00c63d1d3c8c0d19e0f92b5e83bd231481419"]);
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 — Venus Stealer

False Positive Guidance

Here are 4 specific false positive scenarios and their corresponding filters for the ThreatFox: Venus Stealer IOCs detection rule in an enterprise environment:

Scenario: Antivirus Definition Updates via Scheduled Tasks
- Context: Enterprise endpoints often run scheduled tasks (e.g., Task Scheduler on Windows or cron jobs on Linux) that pull the latest threat intelligence feeds from security vendors like CrowdStrike, SentinelOne, or Microsoft Defender. These updates frequently download and hash new IOC lists that may temporarily match the specific file hashes or URLs associated with the Venus Stealer signature before being fully ingested by the SIEM’s threat library.
- Filter/Exclusion: Exclude alerts where the source process is a known security agent updater (e.g., C:\Program Files\SentinelOne\Agent\UpdateService.exe or msiexec.exe running under the SYSTEM account) and the destination URL matches the vendor’s update domain pattern (e.g., *.sentinelone.net, *.microsoft.com).
Scenario: Automated Backup and Archiving Jobs
- Context: Enterprise backup solutions like Veeam, Commvault, or Rubrik perform nightly scans that hash large volumes of data. If the Venus Stealer IOCs include specific file hashes (SHA256) that happen to match legitimate archived configuration files, log bundles, or compressed database dumps being processed by these tools, the rule may trigger on the backup agent’s network traffic rather than a malicious infection.
- Filter/Exclusion: Create an exclusion for processes belonging to known backup suites (e.g., Veeam.Backup.Service.exe, CommServe.exe) where the event type is “File Access” or “Network Connection” and the user context is a dedicated service account (e.g., DOMAIN\BackupSvc).
**Scenario: Software Deployment