mscorsvw.exe

by Microsoft
Runtime

Summary

.NET Framework Optimization Service worker process. It pre-compiles .NET assemblies into native code in the background to improve application startup performance. It is the worker process spawned by ngen.exe to perform the actual compilation work.

mscorsvw.exe is the 16th most commonly executed Windows program in EchoTrail's dataset, observed 4,629,761 times across enterprise environments. It typically runs from C:\Windows\Microsoft.NET\Framework64\v4.0.30319 and it is most often launched by ngen.exe.

16th
most commonly executed Windows program
4,629,761
observed executions
high
statistical confidence

Behavior

Top Paths

  • C:\Windows\Microsoft.NET\Framework64\v4.0.3031955.26%
  • C:\Windows\Microsoft.NET\Framework\v4.0.3031944.74%
  • C:\Windows\Microsoft.NET\Framework\v2.0.50727<0.01%

Top Hashes (SHA256)

  • 101c3e900ff5f2d29ac49dff4b95281637cf10aa8a19a6c84741bb5019aff29418.89%
  • c35cfd9ab9897ce16a6a33bc92d9a49b66c6d9949fd9250acd6bcee4c32c63d815.36%
  • 60def9905f16bd5d10684afea17ab3a9accdd8ba4a6e06240e84e3acb5f94e3d7.09%
  • da1087ba2641efd77d85e5838aeb6c333e80caa9f24c889fd2de2e0b58f8d1a56.96%
  • 097b622bfbc2b6717f0a7d01ffba0aa1a2a1d7e4b298df696250faa164ebc1fb6.29%
  • 26175f1c85658ba787741fa7c7b297d105b985742e640201cb38fd6b3c17f0385.35%
  • 70de04ea3453256d5153f19681d56d2f59bfd9a1ee01a6d1340e8ac5dfca20c84.98%
  • 393729c6f0e4d018039fc0c81c6b3740d43224b2f5889c2d3376c94ef09985744.39%
  • 3e5099f573601926e59862fba2495974688e72677c73f10e4c99e26a76cdcf374.33%
  • ab17fe71cb14e54dbdd64d6a3a96ab7a84b4f2024aeeac3614659022c2bce0303.65%

Process Ancestry

Top Grandparents

Top Parents

Top Children

Rare or environment-specific process names are omitted from ancestry tables. Percentages are of all observed relationships.

Security Analysis

What does mscorsvw.exe normally do?

Located in C:\Windows\Microsoft.NET\Framework64\v4.0.30319 or C:\Windows\Microsoft.NET\Framework\v4.0.30319. Launched by ngen.exe, other mscorsvw.exe instances (worker spawning), or services.exe (when running as a service). High CPU usage during compilation is expected and temporary.

When is mscorsvw.exe suspicious?

Running from a non-.NET Framework path. Launched by unusual parents. Spawning shells or network tools.

How do attackers abuse mscorsvw.exe?

Not commonly abused. Malware could potentially masquerade as mscorsvw.exe to explain high CPU usage.

Detection guidance

Low priority. Validate path is within .NET Framework directories.

False positive notes

High CPU usage is normal and expected — it is compiling .NET assemblies. Bursts of activity after Windows updates or application installations are standard.

Related Processes

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Data from EchoTrail's dataset of ~346M Windows process executions. Last extracted 2026-08-04.