Our call: Is NemuDownloader.exe safe?Safe
This file is a legitimate installer for the MuMu Player emulator, signed by NetEase, and the single engine detection is likely a heuristic false positive.
- The file has a valid code signature from Netease Interactive Entertainment Pte. Ltd..Observed · Code-signing metadata
- 1 of 75 antivirus engines flagged the file, including DeepInstinct.Observed · Antivirus analysis
- The hash has been submitted 943 times from 853 sources.Derived · Saved report facts
0b849c3c8c83a93c0f…c322ffbb13Recommended next actions
Before running
Run it only when it came from the developer's official site or another source you independently trust.
If you already ran it
Keep normal device protection enabled and stop if the file behaves unexpectedly.
Coverage & freshness
Complete means the check returned a usable result. It does not mean the file is safe.
Antivirus
Complete1 of 75 engines flagged the file.
Sandbox
Complete1 isolated runtime environment contributed observations.
Network
Partial4 runtime contacts were observed without a completed reputation cross-check.
YARA
Complete1 signature or behavior rule matched.
External intel
Complete3 of 3 independent reference sources completed.
Attack story
Runtime observations grouped by analysis stage. Arrows organize the stages; they do not claim chronology or causality.
Input file
The submitted object
- FileObserved
NemuDownloader.exe
0b849c3c8c83a93c0f4c73f54132823734583f1135271ee5e14375c322ffbb13
01Uploaded file
Processes
Runtime execution
- ProcessObserved
Observed process
C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\nemu-downloader.exe
02Isolated runtime analysis - ProcessObserved
Observed process
C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\crashpad_handler.exe --no-rate-limit --database=C:\Users\<USER>\AppData\Local\NemuServer\.sentry-native --metrics-dir=C:\Users\<USER>\AppData\Local\NemuServer\.sentry-native --url=https://sentry.netease.com:443/api/325/minidump/?sentry_client=sentry.native/0.5.0&sentry_key=d7282c50f1b64296835edf7d19667322 --attachment=C:\Users\<USER>\AppData\Local\NemuServer\.sentry-native\0e42eb97-fa6d-4b12-7f2b-c33db4522e10.run\__sentry-event --attachment=C:\Users\<USER>\AppData\Local\NemuServer\.sentry-native\0e42eb97-fa6d-4b12-7f2b-c33db4522e10.run\__sentry-breadcrumb1 --attachment=C:\Users\<USER>\AppData\Local\NemuServer\.sentry-native\0e42eb97-fa6d-4b12-7f2b-c33db4522e10.run\__sentry-breadcrumb2 --initial-client-data=0x254,0x258,0x25c,0x228,0x260,0x71874800,0x71874818,0x71874828
03Isolated runtime analysis - +1 more recorded observation in Analyst mode
Files
Created or changed
- Written fileObserved
config.ini
C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\config.ini
04Isolated runtime analysis - Written fileObserved
skin.zip
C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\skin.zip
05Isolated runtime analysis - +1 more recorded observation in Analyst mode
Network
Hosts contacted
- Contacted hostObserved
8.8.8.8
Contact observed during runtime.
06Isolated runtime analysis - Contacted hostObserved
34.36.47.246
Contact observed during runtime.
07Isolated runtime analysis - +1 more recorded observation in Analyst mode
7 recorded facts from one runtime window. Every fact remains independently traceable in Analyst mode.
Why these facts are shown
Each statement identifies whether it was directly recorded or derived from saved scan facts.
- 01
The file has a valid code signature from Netease Interactive Entertainment Pte. Ltd..
ProvenanceObservedSourceCode-signing metadataObserved at - 02
1 of 75 antivirus engines flagged the file, including DeepInstinct.
Verdict inputView chapterProvenanceObservedSourceAntivirus analysisObserved at - 03
The hash has been submitted 943 times from 853 sources.
ProvenanceDerivedSourceSaved report factsObserved at - 04
Scanned file: NemuDownloader.exe — 0b849c3c8c83a93c0f4c73f54132823734583f1135271ee5e14375c322ffbb13
ProvenanceObservedSourceUploaded fileObserved at - 05
Observed process — C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\nemu-downloader.exe
ProvenanceObservedSourceIsolated runtime analysisObserved at - 06
Observed process — C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\crashpad_handler.exe --no-rate-limit --database=C:\Users\<USER>\AppData\Local\NemuServer\.sentry-native --metrics-dir=C:\Users\<USER>\AppData\Local\NemuServer\.sentry-native --url=https://sentry.netease.com:443/api/325/minidump/?sentry_client=sentry.native/0.5.0&sentry_key=d7282c50f1b64296835edf7d19667322 --attachment=C:\Users\<USER>\AppData\Local\NemuServer\.sentry-native\0e42eb97-fa6d-4b12-7f2b-c33db4522e10.run\__sentry-event --attachment=C:\Users\<USER>\AppData\Local\NemuServer\.sentry-native\0e42eb97-fa6d-4b12-7f2b-c33db4522e10.run\__sentry-breadcrumb1 --attachment=C:\Users\<USER>\AppData\Local\NemuServer\.sentry-native\0e42eb97-fa6d-4b12-7f2b-c33db4522e10.run\__sentry-breadcrumb2 --initial-client-data=0x254,0x258,0x25c,0x228,0x260,0x71874800,0x71874818,0x71874828
ProvenanceObservedSourceIsolated runtime analysisObserved at - 07
File written: config.ini — C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\config.ini
ProvenanceObservedSourceIsolated runtime analysisObserved at - 08
File written: skin.zip — C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\skin.zip
ProvenanceObservedSourceIsolated runtime analysisObserved at - 09
Contacted host: 8.8.8.8 — Contact observed during runtime.
ProvenanceObservedSourceIsolated runtime analysisObserved at - 10
Contacted host: 34.36.47.246 — Contact observed during runtime.
ProvenanceObservedSourceIsolated runtime analysisObserved at
Intelligence
The saved assessment, checked against the scan evidence and recorded coverage.
The reasoning behind this verdict
This section explains the evidence supporting the verdict and keeps conflicting or missing signals visible.
Our analysis indicates this file is a legitimate component of the MuMu Player emulator. It is digitally signed by the official developer, NetEase, and the single detection by a tier-2 engine is consistent with common false positives for installer software.
The file is a signed installer for a well-known emulator. While one engine flagged it, the lack of consensus among tier-1 engines and the absence of malicious sandbox behavior strongly suggest it is safe. The observed system-info checks are standard for emulator installation and hardware compatibility verification. We have found no evidence of malicious activity or unauthorized network communication.
What We Detected
The file 'NemuDownloader.exe' is a signed installer for the MuMu Player emulator. Our analysis shows it is digitally signed by 'Netease Interactive Entertainment Pte. Ltd.', which matches the expected publisher for this software. Only 1 out of 75 engines flagged the file, and no tier-1 engines identified it as a threat.
Threat Behavior
The file performs standard installer activities, including extracting DLLs and checking system hardware (e.g., Hyper-V status, baseboard information). These actions are typical for emulator setup processes to ensure compatibility. While the file makes direct IP connections, these are consistent with legitimate update and download mechanisms for such software.
What To Do Now
This file appears to be a legitimate installer. You may proceed with the installation if you obtained it from an official source. As a general security practice, always ensure you are downloading software from the developer's official website to avoid potential tampering.
Where this verdict could be wrong2 caveats
- One tier-2 engine (DeepInstinct) flagged the file as malicious, which may be a heuristic false positive common in installers that perform system-level checks.
- The file performs system-info discovery (e.g., 'ColaBoxChecker.exe /baseboard'), which can be flagged by security tools as suspicious even when used for legitimate hardware compatibility checks.
These are the assessment's weak points. If you believe one applies to your file, report the verdict and we'll re-review it.
- Digitally signed by a known, reputable publisher (Netease Interactive Entertainment Pte. Ltd.)
- Zero detections from all 17 tier-1 antivirus engines
- Common prevalence in our network, indicating widespread legitimate use
The file is safe to use. Ensure you have downloaded it from the official MuMu Player website.
Behavior
Plain-English impact first, then the observed runtime evidence.
What this file did when executed
This file was detonated in 1 sandbox and its runtime behaviour was observed.
Adversary techniques mapped to the MITRE ATT&CK framework.
- 8.8.8.8
- 34.36.47.246
- 104.94.117.210
- 162.159.36.2
- C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\config.ini
- C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\skin.zip
- C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\nemu-downloader.exe
- C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\MuMuDownloader.exe
- C:\Users\<USER>\AppData\Local\Temp\7z3421FAD8\msvcp_win.dll
- C:\Users\<USER>\AppData\Local\NemuServer\.sentry-native\0e42eb97-fa6d-4b12-7f2b-c33db4522e10.run\session.json
- nemu-downloader-run-mutex
- ColaBoxChecker:config
Files this sample writes at runtime
This file drops 10 children at runtime. None are currently flagged malicious in our cache.
- 17748d9e00fedaf94c90…ea69c1Never scannednever seen before
- aa40840b724a3c1e1d2d…454c10Never scannednever seen before
- e5b377e0fe13e27a2172…05bff5Never scannednever seen before
- 7b3463c16416c93d9b8b…658a3cNever scannednever seen before
- d56c631b0f4f70bdeebc…d22399Never scannednever seen before
- da48178bbdd98fa8906b…09fcdaNever scannednever seen before
- 6ee46c6b6727eb77bcbc…58844eNever scannednever seen before
- dcb9cf7e31d6772434c6…88294cNever scannednever seen before
- b15964d49a2c5219e092…4e401fNever scannednever seen before
- 582e87ade6dac2588441…74c74bNever scannednever seen before
Detection & Forensics
Consensus, attribution, signatures, code structure, prevalence, and identity.
Detection sources at a glance
The available sources did not agree on a named threat category.
MalwareBazaar, YARAify, and CIRCL hashlookup completed and returned no entries for this hash.
Signatures and behavior heuristics
Behavioral heuristics matched patterns associated with malware. Corroborating evidence determines how much weight they carry.
The sample contacted an external IP address directly and no application domain was recorded. Direct-IP traffic also occurs in legitimate installers and infrastructure, so this is supporting context only and requires corroboration from host reputation and other runtime evidence.
Evidence34.36.47.246 · 104.94.117.210 · 162.159.36.2
1 of 75 engines flagged this file
View all 75 engine results
Section entropy & packers
No high-entropy executable section or known packer signature was detected. Data and resource sections can still have high entropy without indicating packed code.
How widely this file has been seen
Lots of people are uploading this but it's recent — typical of newly-released legitimate software. Low prior for malware.
Fingerprint and provenance
- File name
- NemuDownloader.exe
- Format
- Win32 EXE
- Code signing
- Signature valid: Netease Interactive Entertainment Pte. Ltd.
- Size
- 5.8 MB
- Last analyzed
- Aug 1, 2026, 10:37 AM UTC
0b849c3c8c83a93c0f4c73f54132823734583f1135271ee5e14375c322ffbb13Safety & FAQ
Complete recovery guidance and answers for the next decision.
What to do now
This file appears low risk based on the evidence available now.
Run it only when it came from the developer's official site or another source you independently trust.
A clean result reduces known risk, but it cannot guarantee that every new or targeted threat has been detected.
Keep your antivirus and Windows updates switched on so you stay protected.