Suspicious
Unsigned Windows utility exhibits process injection (T1055) and LSASS access in analysis but clean across our antivirus network.
462971f3f033dadff6…4902870efeThe verdict, reasoned out.
Not a rules engine. The MT AI Engine reads every signal we collected, weighs them against history, and commits to an answer.
Strong behavioural signals from sandbox analysis indicate offensive techniques typically seen in hacktools or trojans, including injection and privilege manipulation. The file's unsigned status and DLL-misnamed EXE format add concern, but perfect clean scan results from high-coverage engines weigh against immediate malice. Embedded Costura .NET assemblies and GUI-related artifacts point to a legitimate utility like a context menu manager. Absent engine consensus or bad network/drops, this remains borderline warranting caution.
Each signal cites a concrete token from the evidence the arbiter saw — engine name, MITRE technique, signer string, or an exact count.
triggeredHeuristics[0].rule='MalwareTips.Synth.ProcessInjection' fired=true severity=high evidence='C:\Windows\System32\svchost.exe -k NetworkService -p'
triggeredHeuristics[1].rule='MalwareTips.Synth.CredentialDumper' fired=true severity=medium evidence='C:\Windows\system32\lsass.exe'
behaviour.offensiveCount=2 (T1055, T1134); sandboxCount=1 but hasMaliciousSandboxVerdict=false
engines.reporting=71/76 total with 0 malicious across all tiers
mutexesCreated includes 'CosturaEE69E02B32099E67E2834169649026A6' confirming .NET Costura embedding
- Undetected by 71/76 engines incl. tier1 (Kaspersky, ESET, BitDefender)
- No malicious sandbox verdict
- No malicious dropped children or contacted hosts
- Costura .NET embedding with graphics libs (SkiaSharp)
- Unsigned PE executable
- Process injection (T1055, svchost.exe)
- LSASS access (credential dumper shape)
- Access token manipulation (T1134)
- DLL filename on EXE fileType
- Recent file (29 days old)
Treat as suspicious and isolate immediately. Monitor system for unusual process injection or credential access; consider full scan and removal if not a trusted utility.
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.
- C:\Users\<USER>\AppData\Local\Temp\Costura\EE69E02B32099E67E2834169649026A6\64\av_libglesv2.dll
- C:\Users\<USER>\AppData\Local\Temp\Costura\EE69E02B32099E67E2834169649026A6\64\libharfbuzzsharp.dll
- C:\Users\<USER>\AppData\Local\Temp\Costura\EE69E02B32099E67E2834169649026A6\64\libskiasharp.dll
- C:\Users\user\AppData\Local\Microsoft\Windows\Caches
- C:\Users\user\AppData\Local\Temp\Costura
- CosturaEE69E02B32099E67E2834169649026A6
- Local\SessionImmersiveColorMutex
- Global\OneSettingQueryMutex+compat+encapsulation
- \Sessions\1\BaseNamedObjects\CosturaEE69E02B32099E67E2834169649026A6
- \Sessions\1\BaseNamedObjects\DBWinMutex
Files this sample writes at runtime
This file drops 3 children at runtime. None are currently flagged malicious in our cache.
- f13d0dae00a598620a43…cd996cNever scannednever seen before
- 85b3aee47c0e0eaf3a5e…7695aeNever scannednever seen before
- 3268b1b2de384d00ed77…d63b52Never scannednever seen before
YARA + heuristic rules that fired
A researcher-curated or high-severity heuristic rule matched this sample. These rules target specific malware families and are near-definitive.
MITRE T1055 (Process Injection) observed — CreateRemoteThread / APC / reflective-DLL injection. The payload is being smuggled into a legitimate process to bypass AV hooks.
EvidenceC:\Windows\System32\svchost.exe -k NetworkService -pSandbox observed process activity targeting LSASS (Windows credential store). Legitimate software has no business reading LSASS memory — this is Mimikatz-shape behaviour.
EvidenceC:\Windows\system32\lsass.exe
0 detections across 76 engines
Section entropy & packers
Section-level entropy and packer detection from the PE header. Nothing suspicious here — entropy is within the normal range for unpacked code.
How often this file shows up in the wild
Moderate prevalence — neither rare nor common. No strong prior applies.
Forensic fingerprint
- File name
- Windows11ContextMenuManager.dll
- Size
- 27.26 MB
- MIME type
- (unknown)
- Detected type
- Win32 EXE
- SHA-256
- 462971f3f033dadff698db140d9c55bb09e1e786f0ae9b228f99e84902870efe
- MD5
- c8c86135a9fc0907ac4da01f395720e8
- SHA-1
- 4ad91c75278a10ffd7dbdaead22785722161948a
- PE imphash
- e556870483f021b664787e6000df12c5
- First seen (VT)
- 3/26/2026, 5:58:23 AM
- Last analysis (VT)
- 4/18/2026, 7:39:10 AM
- First scan (MalwareTips)
- 4/24/2026, 6:15:01 AM
- Last scan (MalwareTips)
- 4/24/2026, 6:15:01 AM
Reviews & malware reports(0)
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