ThreatFox: Venus Stealer IOCs

Hunt Hypothesis

This hunt detects adversary behavior where threat actors utilize specific indicators of compromise (IOCs) linked to the Venus Stealer malware to exfiltrate sensitive credentials and data from endpoints. A SOC team should proactively hunt for these IOCs in Azure Sentinel to identify early-stage infections that may evade standard signature-based detection, thereby preventing potential lateral movement and data loss before full compromise occurs.

IOC Summary

Malware Family: Venus Stealer Total IOCs: 6 IOC Types: sha1_hash, md5_hash, sha256_hash

Type	Value	Threat Type	First Seen	Confidence
md5_hash	`65cef1e97cc1dbaa4fe794599838e434`	payload	2026-08-08	95%
sha256_hash	`4115dfac942c3e99fa356fcd89cb30ecbeb8156da57b1fb0d8c8270699b6417b`	payload	2026-08-08	95%
sha1_hash	`4b2314b9fcae13e7c9e93ac93d08404bddea1a90`	payload	2026-08-08	95%
sha1_hash	`50e9dd0c02bc1927862be248b90d3d9bdb0fcc86`	payload	2026-08-08	95%
md5_hash	`a216558b0c9403010e3682e37bad4b0c`	payload	2026-08-08	95%
sha256_hash	`e234be44eeafaf0250d9ef2cef198e223264e1541cff78d30a98163c5a7dde67`	payload	2026-08-08	95%

KQL: Hash Hunt

// Hunt for files matching known malicious hashes
// Source: ThreatFox - Venus Stealer
let malicious_hashes = dynamic(["65cef1e97cc1dbaa4fe794599838e434", "4115dfac942c3e99fa356fcd89cb30ecbeb8156da57b1fb0d8c8270699b6417b", "4b2314b9fcae13e7c9e93ac93d08404bddea1a90", "50e9dd0c02bc1927862be248b90d3d9bdb0fcc86", "a216558b0c9403010e3682e37bad4b0c", "e234be44eeafaf0250d9ef2cef198e223264e1541cff78d30a98163c5a7dde67"]);
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 for the ThreatFox: Venus Stealer IOCs detection rule, along with targeted filtering strategies:

Scenario: Automated Security Tool Updates
- Context: Enterprise Endpoint Detection and Response (EDR) agents like CrowdStrike Falcon or Microsoft Defender for Endpoint frequently download definition updates from cloud repositories. If the update server’s IP address or the specific hash of a new definition package matches one of the Venus Stealer IOCs, the rule triggers on every agent refresh cycle across thousands of machines.
- Filter/Exclusion: Create an exclusion based on the process name C:\Program Files\CrowdStrike\FalconSensor\csfalcon.exe (or equivalent for Defender) and exclude traffic originating from known update server IP ranges (e.g., 13.107.xx.xx) or specific file hashes that are verified as benign in the threat intelligence feed.
Scenario: Scheduled Backup Jobs
- Context: Automated backup solutions such as Veeam Backup & Replication or Rubrik often run scheduled jobs during off-hours to archive data to cloud storage (e.g., AWS S3, Azure Blob). These tools may utilize specific network ports or certificate fingerprints that overlap with the Venus Stealer IOCs, particularly if they use a shared SSL certificate authority or a common communication port.
- Filter/Exclusion: Exclude alerts where the source process is Veeam.Backup.Service.exe or RubrikAgent.exe and the destination IP belongs to the organization’s designated backup storage subnet (e.g., 10.50.xx.xx). Additionally, filter by time-of-day if backups are strictly scheduled between 02:00 and 04:00 UTC.
Scenario: Software Deployment via Configuration Management
- **Context