MpSigStub.exe

by Microsoft
Endpoint Security

Sources: 300M+ executions observed in the wild.

Summary

Microsoft Protection Signature Stub - temporary process used during Windows Defender signature (definition) updates.

MpSigStub.exe is the 322nd most commonly executed Windows program in EchoTrail's dataset, observed 28,452 times across enterprise environments. It typically runs from C:\Windows\System32 and it is most often launched by AM_Delta.exe.

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322nd
most commonly executed Windows program
28,452
observed endpoint executions

Behavior

Top Paths

  • C:\Windows\System3292.99%
  • C:\Windows\Temp\...4.2%
  • C:\Windows\SoftwareDistribution\Download\Install1.31%
  • C:\Windows\SERVIC~1\NETWOR~1\AppData\Local\Temp\...0.96%
  • C:\Windows\SERVIC~2\NETWOR~1\AppData\Local\Temp\...0.13%
  • C:\Windows\SERVIC~3\NETWOR~1\AppData\Local\Temp\...0.05%
  • C:\Windows\SystemTemp\1D37F759-DEF1-44D2-9C8A-79EEFC14BA8B0.01%
  • C:\Users\...<0.01%
  • C:\Windows\SystemTemp\0193E21E-75F2-4731-8810-8FC9A088E09B<0.01%
  • C:\Windows\SystemTemp\0485A7D1-B22B-4841-BB7E-4095EBB74A40<0.01%

Top Hashes (SHA256)

  • fa42b9b84754e2e8368e8929fa045be86dbd72678176ee75814d2a16d23e5c2623.06%
  • d0772bfb0687e068d4d21749c90dbac7fb7f71f74f3a8caf6d69cac483a1c17f12.49%
  • 0bc408c801441239f72d7df3dd6edbcdfb5313d6ae5a04c0a13e8c2dfc39f6d810.45%
  • 489663a32ce72a60fb45d6f88a391ef17eb1aa97554a3fd7867c8f6decb35bc79.87%
  • f3bf989add4b18e246cdab149df46b71c8fe5315875ffc988b7289be737d4ec09.82%
  • 0bb339c22fb53e6bc8f8475590d8549f5432f45cf61337db15d0d2ff552324bb8.29%
  • a20a90f00b76ff248107fc105705cfe0545530ba0cfaa25f3eb7afab769af04c8.06%
  • e0355c48c099a023bcebf2d477e476e9d57657025f5a0658a2bd00e75d89f95f4.42%
  • 896f1793ca8bda909a71217f41a93af5a06354c1ea9ea81c975d429224b28e192.95%
  • 071b0d3a08503a8b88aeeda1d20f371a563377028f6e252dc66cce60ab8f823e2.29%

Process Ancestry

Top Grandparents

Top Parents

Top Children

Security Analysis

What does MpSigStub.exe normally do?

Runs briefly during Defender definition updates to extract and apply new signature files.

When is MpSigStub.exe suspicious?

Persistent execution (should be brief). Running from non-standard paths.

False positive notes

Brief execution during Defender updates is normal.

Related Processes

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