vc_redist.x64.exe installation hangs indefinitely during docker build on windowsservercore-ltsc2019 after July 2026 patch

[cyuz]

Describe the bug

Starting from the July 2026 Patch Tuesday update, running the Visual C++ Redistributable installer (vc_redist.x64.exe) with silent flags (/quiet /norestart) inside a Windows Container build session (docker build / Session 0) hangs indefinitely.

This issue specifically triggers on the latest windowsservercore-ltsc2019 base images updated this month. Builds that used to pass successfully prior to the July 2026 security rollout are now 100% deadlocked.

Environment

• Base Image: mcr.microsoft.com/dotnet/aspnet:9.0-windowsservercore-ltsc2019 (Latest floating tag as of July 2026)
• Host OS: Windows Server 2019 / Windows 11 (with July 2026 cumulative updates)
• Installer Version: VC++ Redistributable 2015-2022 (vc_redist.x64.exe) downloaded from https://aka.ms/vs/17/release/vc_redist.x64.exe

Dockerfile to Reproduce

FROM mcr.microsoft.com/dotnet/aspnet:9.0-windowsservercore-ltsc2019 AS base

# Download the installer
ADD https://aka.ms/vs/17/release/vc_redist.x64.exe C:/vc_redist.x64.exe

# The build process hangs here forever without any exit code or log output
RUN powershell -Command \
    Start-Process -FilePath 'C:\vc_redist.x64.exe' -ArgumentList '/quiet', '/norestart' -Wait

WORKDIR /app

Which .NET image(s) are you using?

mcr.microsoft.com/dotnet/aspnet@sha256:b84168fc691dd47235997f251f14a39e0e92b8b522bb8bb7abeadaf34dc74e0c

Steps to reproduce

No response

Other information

No response

Output of docker version

Client: Mirantis Container Runtime
 Version:           20.10.7
 API version:       1.41
 Go version:        go1.13.15
 Git commit:        40ef3b6
 Built:             08/19/2021 18:54:26
 OS/Arch:           windows/amd64
 Context:           default
 Experimental:      true

Server: Mirantis Container Runtime
 Engine:
  Version:          20.10.7
  API version:      1.41 (minimum version 1.24)
  Go version:       go1.13.15
  Git commit:       e1bf5b9c13
  Built:            08/19/2021 18:53:20
  OS/Arch:          windows/amd64
  Experimental:     false

Output of docker info

Client:
 Context:    default
 Debug Mode: false
 Plugins:
  app: Docker Application (Docker Inc., v0.8.0)
  cluster: Manage Mirantis Container Cloud clusters (Mirantis Inc., v1.9.0)
  registry: Manage Docker registries (Docker Inc., 0.1.0)

Server:
 Containers: 0
  Running: 0
  Paused: 0
  Stopped: 0
 Images: 137
 Server Version: 20.10.7
 Storage Driver: windowsfilter
  Windows:
 Logging Driver: json-file
 Plugins:
  Volume: local
  Network: ics internal l2bridge l2tunnel nat null overlay private transparent
  Log: awslogs etwlogs fluentd gcplogs gelf json-file local logentries splunk syslog
 Swarm: inactive
 Default Isolation: process
 Kernel Version: 10.0 17763 (17763.1.amd64fre.rs5_release.180914-1434)
 Operating System: Windows Server 2019 Datacenter Version 1809 (OS Build 17763.9020)
 OSType: windows
 Architecture: x86_64
 CPUs: 2
 Total Memory: 4GiB
 Name: OSEContainerAge
 ID: KTHW:PLDF:ANZN:P6AJ:I66D:2ZHR:SVYL:5CS3:X2U7:OGO7:YBYS:JCGI
 Docker Root Dir: C:\ProgramData\docker
 Debug Mode: false
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false

[sisoctagon]

FROM mcr.microsoft.com/dotnet/aspnet:9.0-windowsservercore-ltsc2019 AS base

# Download the installer
ADD https://aka.ms/vs/17/release/vc_redist.x64.exe C:/vc_redist.x64.exe

# The build process hangs here forever without any exit code or log output
RUN powershell -Command \
    Start-Process -FilePath 'C:\vc_redist.x64.exe' -ArgumentList '/quiet', '/norestart' -Wait

WORKDIR /app

Client: Mirantis Container Runtime
 Version:           20.10.7
 API version:       1.41
 Go version:        go1.13.15
 Git commit:        40ef3b6
 Built:             08/19/2021 18:54:26
 OS/Arch:           windows/amd64
 Context:           default
 Experimental:      true

Server: Mirantis Container Runtime
 Engine:
  Version:          20.10.7
  API version:      1.41 (minimum version 1.24)
  Go version:       go1.13.15
  Git commit:       e1bf5b9c13
  Built:            08/19/2021 18:53:20
  OS/Arch:          windows/amd64
  Experimental:     false
Client:
 Context:    default
 Debug Mode: false
 Plugins:
  app: Docker Application (Docker Inc., v0.8.0)
  cluster: Manage Mirantis Container Cloud clusters (Mirantis Inc., v1.9.0)
  registry: Manage Docker registries (Docker Inc., 0.1.0)

Server:
 Containers: 0
  Running: 0
  Paused: 0
  Stopped: 0
 Images: 137
 Server Version: 20.10.7
 Storage Driver: windowsfilter
  Windows:
 Logging Driver: json-file
 Plugins:
  Volume: local
  Network: ics internal l2bridge l2tunnel nat null overlay private transparent
  Log: awslogs etwlogs fluentd gcplogs gelf json-file local logentries splunk syslog
 Swarm: inactive
 Default Isolation: process
 Kernel Version: 10.0 17763 (17763.1.amd64fre.rs5_release.180914-1434)
 Operating System: Windows Server 2019 Datacenter Version 1809 (OS Build 17763.9020)
 OSType: windows
 Architecture: x86_64
 CPUs: 2
 Total Memory: 4GiB
 Name: OSEContainerAge
 ID: KTHW:PLDF:ANZN:P6AJ:I66D:2ZHR:SVYL:5CS3:X2U7:OGO7:YBYS:JCGI
 Docker Root Dir: C:\ProgramData\docker
 Debug Mode: false
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false

[lbussell]

Hi @cyuz, @sisoctagon - thanks for filing the issue, I am trying to repro this locally.
In the meantime, it looks like there are some related issues, all to do with the latest update for Server 2019:

• Performance issues noticed after upgrading to dotnet/framework/runtime:4.8-20260714-windowsservercore-ltsc2019 microsoft/dotnet-framework-docker#1314
• Containerized Azure Data Factory Self-Hosted Integration Runtime works on Server Core ltsc2019 build 17763.8511 but not 17763.9020 microsoft/Windows-Containers#641

[lbussell]

@cyuz, @sisoctagon - please take a look at my comment on the .NET Framework issue for a potential workaround.