ThreatFox: Venus Stealer IOCs

Hunt Hypothesis

This hunt targets adversary behavior consistent with the Venus Stealer infostealer, specifically monitoring for network connections and file artifacts matching its three known Indicators of Compromise (IOCs). Proactively hunting for these signals in Azure Sentinel is critical to rapidly identify early-stage data exfiltration attempts before they escalate into significant credential theft or lateral movement incidents.

IOC Summary

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

Type	Value	Threat Type	First Seen	Confidence
sha1_hash	`ac0ba770904dedc4cd0f713b89359048325993ef`	payload	2026-07-10	95%
md5_hash	`c4f11447afc4928a9ce8843fc81cb25c`	payload	2026-07-10	95%
sha256_hash	`1fc2634ee7f9bdddc44bdb2424e898e71d844b8935c2d9c6bb208a6a5befba9e`	payload	2026-07-10	95%

KQL: Hash Hunt

// Hunt for files matching known malicious hashes
// Source: ThreatFox - Venus Stealer
let malicious_hashes = dynamic(["ac0ba770904dedc4cd0f713b89359048325993ef", "c4f11447afc4928a9ce8843fc81cb25c", "1fc2634ee7f9bdddc44bdb2424e898e71d844b8935c2d9c6bb208a6a5befba9e"]);
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 four specific false positive scenarios for the ThreatFox: Venus Stealer IOCs detection rule in an enterprise environment, along with recommended filters or exclusions:

Antivirus Quarantine and Scanning Operations
- Scenario: Enterprise Endpoint Detection and Response (EDR) solutions like CrowdStrike Falcon, Microsoft Defender for Endpoint, or SentinelOne frequently download definition updates or scan archives that contain the specific IOCs associated with Venus Stealer. When these tools extract or analyze a known malicious sample within their quarantine sandbox, they may generate file creation or network connection events matching the detection logic, even though no active infection exists on the host.
- Filter/Exclusion: Exclude processes running under the context of major EDR vendors (e.g., C:\Program Files\CrowdStrike\, C:\ProgramData\Microsoft\Windows Defender\) and filter out events where the parent process is an AV scanner service (e.g., MsMpEng.exe, csagent.exe).
Security Information and Event Management (SIEM) Log Parsing
- Scenario: SIEM platforms such as Splunk, IBM QRadar, or Microsoft Sentinel often ingest large volumes of logs from various sources. If the detection logic relies on parsing specific file hashes or network URLs, the SIEM’s own internal indexing processes or log forwarders (like Syslog-ng or Fluent Bit) might process a reference dataset containing Venus Stealer IOCs for correlation testing. This results in legitimate “file access” or “network flow” events that mimic an active threat detection.
- Filter/Exclusion: Create a filter to exclude source hosts identified as SIEM collectors, log forwarders, or management servers (e.g., Hostnames starting with SIEM-, LOG-FWD-) and restrict the rule scope to