GridinSoft Threat Intelligence
poobserver.exe threat report
GridinSoft Anti-Malware detection
Detected by GridinSoft before you download
The current ThreatInfo record shows this exact file hash detected as Risk.Downloader. Download GridinSoft Anti-Malware to scan the device, confirm whether this file is present, and remove the detected object if it is found.
- Detection name
- Risk.Downloader
- Recommended action
- Scan and remove
- Last analysis
- 2026-05-26 18:01:02 (a day ago)
- File hash
- 4a3c1533c3e0c90f78995c418a5080ab
Why it matters
Why GridinSoft flags this file
GridinSoft identifies the sample as Risk.Downloader, part of the Risk threat category.
Riskware and dual-use utilities that may be legitimate but require careful review. Related Risk reports help compare this file with nearby detections, publishers, and hashes.
First seen 2025-10-19 23:00:17 (7 months ago); latest analysis 2026-05-26 18:01:02 (a day ago).
Company metadata: UnderSky TreeLeaf Union. Product metadata: USTL Service.
ThreatInfo has seen this file in user or system paths listed below. Unexpected locations increase the need for local verification.
Recommended action
What to do next
- Compare the MD5 above with the file found on the device.
- Check whether the file appears in the observed locations or under one of the alternate names.
- Run GridinSoft Anti-Malware to confirm the detection and remove the file if it is present. Review the Risk category for related samples and common context.
File context
poobserver.exe is a Windows file recorded in the ThreatInfo database. It is associated with USTL Service. The reported company name is UnderSky TreeLeaf Union. The current detection status is Risk.Downloader, based on the latest analysis from 2026-05-26 18:01:02 (a day ago). ThreatInfo groups this verdict with Risk reports for broader family-level investigation.
If poobserver.exe appears on your computer unexpectedly, treat it as suspicious. Check its location, digital signature, and recent system changes before allowing it to run. A full anti-malware scan is recommended when this file is detected as Risk.Downloader.
File Details
| Product Name: | USTL Service |
| Company Name: | UnderSky TreeLeaf Union |
| MD5: | 4a3c1533c3e0c90f78995c418a5080ab |
| Size: | 441 KB |
| First Published: | 2025-10-19 23:00:17 (7 months ago) |
| Latest Published: | 2026-05-26 18:01:02 (a day ago) |
| Status: | Risk.Downloader (on last analysis) | |
| Analysis Date: | 2026-05-26 18:01:02 (a day ago) |
Detection screenshot
The screenshot is a visual record of a GridinSoft Anti-Malware detection for this sample. Use the hash and metadata above as the primary identifiers when comparing the file on your system.
Common Places:
| %commonappdata% |
ThreatInfo has observed poobserver.exe in the locations listed above. Files found in temporary folders, user profile folders, startup locations, or unusual application directories should be reviewed more carefully than files installed under a known program directory.
Geographic signal
Observed country distribution
ThreatInfo has seen poobserver.exe across 3 countries. Use this signal to compare local evidence with where the sample is most often reported.
The strongest geographic signal for this file is Brazil with 72.7% of observed hits. Geographic distribution can help identify targeted campaigns, regional software bundles, or where a file is most commonly reported.
OS Version:
The most common operating system signal for poobserver.exe is Windows 10 with 100.0% of observed hits. If your system differs from the common profile, check whether the file was introduced by a specific installer, archive, or removable device.
Analysis
poobserver.exe is identified as pe for 64-bit systems. The subsystem is Windows GUI. PE header values are useful for triage, especially when they do not match the expected publisher, product, or release timeline.
PE Sections:
Section layout highlights raw-size concentration, repeated names, packer markers, and hashes that can be compared across related samples.
b8e63699783c7e75e8d45b7dca87a27e
0b4a9df8de4d307026cc6b8a8b477b81
b2044ec38f2eafc5a221e8d2f8b459c9
2eb690d96208c7dd4267e5aaef2aca35
468a74cb6d4987eb849e7008b011b67e
f21ae1950f83d6bab5d33a12da87fdc1
77b25807a54f7c6f51a4633f25c2814e
PE section names and hashes can reveal packing, injected resources, or unusual build artifacts. Sections with uncommon names, very large raw data, or hashes that differ from a trusted copy deserve additional review.
Report conclusion
GridinSoft detects this file as Risk.Downloader
This report identifies poobserver.exe by MD5 4a3c1533c3e0c90f78995c418a5080ab. It is part of the Risk report group. If the same file is present on your device, scan the system and remove the detected object after confirming the hash and location.