Weblate has a Server-Side Request Forgery issue

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.0 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N

EPSS

• CVE-2025-66407: 0.24% estimated exploitation activity in the next 30 days; percentile 15.18 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact The Create Component functionality in Weblate allows authorized users to add new translation components by specifying both a version control system and a source code repository URL to pull from. However, the repository URL field is not validated or sanitized, allowing an attacker to supply arbitrary protocols, hostnames, and IP addresses, including localhost, internal network addresses, and local filenames. When the Mercurial version control system is selected, Weblate exposes the full server-side HTTP response for the provided URL. This effectively creates a server-side request forgery (SSRF) primitive that can probe internal services and return their contents. In addition to accessing internal HTTP endpoints, the behavior also enables local file enumeration by attempting file:// requests. While file contents may not always be returned, the application’s error messages clearly differentiate between files that exist and files that do not, revealing information about the…

Published by the source

26 May 2026, 16:41 UTC

Last modified by the source

26 May 2026, 16:45 UTC

Source last checked

26 Oct 2026, 13:41 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-hfpv-mc5v-p9mm

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-hfpv-mc5v-p9mm

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# Patch Next advisory brief: CVE-2025-66407

Advisory: Weblate has a Server-Side Request Forgery issue
IDs: CVE-2025-66407, GHSA-hfpv-mc5v-p9mm
Record: https://patchnext.com/advisories/cve-2025-66407 (revision 2, source checked 26 Oct 2026, 13:41 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.0)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: weblate 5.15. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI weblate: affected < 5.15; fixed in 5.15

## Suggested inspection (read-only)
- `python -m pip show weblate`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on weblate.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-hfpv-mc5v-p9mm (OSV record GHSA-hfpv-mc5v-p9mm lists affected ranges: PyPI weblate >=0 <5.15 (fixed))
- Verified: https://github.com/advisories/GHSA-hfpv-mc5v-p9mm (GitHub-reviewed advisory GHSA-hfpv-mc5v-p9mm lists affected ranges: PyPI weblate >=0 <5.15)

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