wlc may disclose API tokens to project-configured URLs

Impact

wlc could send an unscoped API token to an unintended server when run inside a directory tree containing attacker-controlled project configuration.

If .weblate, .weblate.ini, or weblate.ini defines an API url, and the user supplies a token with WLC_KEY or --key without also pinning the URL, wlc would send the token to the project-configured URL.

Impacted users are those running wlc in untrusted repositories, pull request checkouts, or directories with untrusted ancestor configuration while using WLC_KEY or --key.

Patches

The issue is patched in wlc 2.0.1 via https://github.com/WeblateOrg/wlc/pull/1500.

The fix rejects unscoped keys when the API URL comes from automatically discovered project configuration:

• WLC_KEY now requires WLC_URL.
• --key now requires --url.
• URL-scoped keys in the [keys] configuration section remain supported.

Users should upgrade to wlc 2.0.1 or newer.

Workarounds

Without upgrading, users can avoid the issue by explicitly pinning the API URL whenever using an unscoped key:

WLC_URL=https://hosted.weblate.org/api/ WLC_KEY=... wlc ...

or:

wlc --url https://hosted.weblate.org/api/ --key ... ...

Alternatively, use URL-scoped keys in the [keys] section instead of WLC_KEY or --key, and avoid running wlc with secrets in untrusted checkouts.

• The issue was independently reported by type5afe and visionx7 using HackerOne.