Forgejo <=16.0.3 Critical RCE

You should change the URL to https://codeberg.org/forgejo/forgejo/milestone/139655

> PR: Critical: fix: prevent template expansion from interfering with git repo initialization. When generating a new repository from a template repository, Forgejo clones the template repository, removes the .git folder, performs variable template expansion on files listed in .forgejo/template, and initializes a new git repository. During this process, variable template expansion could be misused in order to create a new .git folder, which git would adopt and incorporate during its initialization of a new git repository. A malicious template repository could be used to read arbitrary data from the Forgejo host, and to execute arbitrary processes on the Forgejo host, as a remote code execution attack. To address this issue, after variable expansion is completed, any existing .git folder is removed from the directory before the git repository is initialized.

Only posting here because I've been asked about it. Gitea is protected against both of these issues.

(bias note: part of project leadership of Gitea)

Edit: As a note, security incidents happen to everyone and we shouldn't shame anyone for reporting them, especially as that'd otherwise cause less issues to be reported overall.

This was my first thought after they disallowed LLM contributions.

They may not use AI to check for vulnerabilities but attackers are going to which puts themselves at the disadvantage.

Relevant change:

   Security bug fixes

    PR: Critical: fix: prevent template expansion from interfering with git repo initialization. When generating a new repository from a template repository, Forgejo clones the template repository, removes the .git folder, performs variable template expansion on files listed in .forgejo/template, and initializes a new git repository. During this process, variable template expansion could be misused in order to create a new .git folder, which git would adopt and incorporate during its initialization of a new git repository. A malicious template repository could be used to read arbitrary data from the Forgejo host, and to execute arbitrary processes on the Forgejo host, as a remote code execution attack. To address this issue, after variable expansion is completed, any existing .git folder is removed from the directory before the git repository is initialized.

The opex and security fine costs of moving off managed services like GitHub/GitLab are catching up.

Since the release notes is currently unreadable due to codeberg rate limits, the two fixes in the release notes are:

https://codeberg.org/forgejo/forgejo/pulls/14301:

*Critical:* fix: prevent template expansion from interfering with git repo initialization. When generating a new repository from a template repository, Forgejo clones the template repository, removes the `.git` folder, performs variable template expansion on files listed in `.forgejo/template`, and initializes a new git repository. During this process, variable template expansion could be misused in order to create a new `.git` folder, which git would adopt and incorporate during its initialization of a new git repository. A malicious template repository could be used to read arbitrary data from the Forgejo host, and to execute arbitrary processes on the Forgejo host, as a remote code execution attack. To address this issue, after variable expansion is completed, any existing `.git` folder is removed from the directory before the git repository is initialized.

https://codeberg.org/forgejo/forgejo/pulls/14301:

ensure authorization reducer is accessed when checking editable PRs in APIs. When editing a git repo contents through Forgejo's API, a specialized security control is used to permit repository maintainers to edit branches that they do not own when an open pull request with the "allow maintainer edit" option is present. This specialized security control did not take into account API-specific security restrictions, such as repo-specific access tokens. As a result, it was possible for an API access token with restricted permission to make modifications outside of that restricted permission. The specialized security control has been updated to take into account API authentication security restrictions.

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So if like me you run a private forgejo instance with closed signups and limited repository creation, you can wait for the update. Otherwise maybe take it off the public internet for a bit?

``` This git endpoint is seeing a high influx of requests for this repository, to preserve the availability of Codeberg your search request will not be processed. Sorry for the inconvenience and please try again later. ```

Any mirror?

If you are self-hosting Forgejo and haven't done it yet, consider creating a Codeberg account and following https://codeberg.org/forgejo/security-announcements/issues

Quick note that this is not an RCE in the typical sense that I can rock up to a Forgejo installation and execute code on the server. The attack vector here is via a template repo specified when initializing a new repo. The template repo could contain malicious code that then executes on the host server. So if you don't create new repos from mystery meat template repos, you should be ok.

Can't load the page but hopefully it's on an endpoint sitting behind my Tinyauth protection.