Adding dotnet:4-alpine image

[Bailey Firman (BaileyFirman)]

Adding alpine support for dotnet, motivated by the large number of image vulnerabilities mostly reported for Debian.
This is a POC PR to hopefully get the ball rolling on this issue: #901 with changes I based off #924

Note: I am using the contents of this new Dockerfile internally instead of FROM mcr.microsoft.com/azure-functions/dotnet:4 in order to meet security requirements, at time of writing there are no vulnerabilities reported when scanning the resulting image.

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[Bailey Firman (BaileyFirman)]

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[Dimitri Kroo (SymbioticKilla)]

Any ETA?

[Dimitri Kroo (SymbioticKilla)]

Tony Choi (@Tonewall) Ahmed ElSayed (@ahmelsayed) Varad Meru (@vrdmr) Tsuyoshi Ushio (@TsuyoshiUshio) Pragna Gopa (@pragnagopa) Anirudh Garg (@anirudhgarg) Bala G (@balag0) CooperLink Ahmed El Sayed (@amamounelsayed) Jameson Z (@VpOfEngineering)

Hi guys!

Cann it be more prioritized?
Debian images have up-to 300 CVEs. It is very hard to check each of them in term of security.
Thanks!

[skowroncdwag]

+1

[David Stark (davidstarkcab)]

+1

[Vivek Jilla (vivekjilla)]

Thank you for taking the time to contribute.

As noted in the repository README, the Azure Functions base-image Dockerfile sources were moved to an internal Microsoft repository in May 2025 and are no longer maintained here. The files and directories targeted by this pull request have therefore been removed, so this change can no longer be merged.

We are closing this pull request as part of cleaning up the repository. This repository will remain available for supported samples and GitHub issues. If the proposed change identifies a problem with a published image or Azure Functions behavior, please open or continue an issue with the relevant details.

We appreciate your contribution and understanding.