CVE-2026-77573: Time-of-check Time-of-use (TOCTOU) Race Condition

Weblate is a web-based continuous localization platform used to manage software translations. In versions prior to 2026.8, a user permitted to manage component repository URLs can perform server-side request forgery against internal services through DNS rebinding during VCS operations. Weblate validates the hostname's first DNS resolution, but the external VCS clients that later connect perform a separate DNS lookup, so an attacker-controlled hostname that initially resolves to a public address can be re-pointed to an internal or private address before the connection is made. By triggering a clone, fetch, push, or similar remote operation, the attacker can cause Weblate to reach internal VCS-compatible services and potentially expose private repository contents. Installations that permit untrusted repository hostnames while using VCS_RESTRICT_PRIVATE=True are affected. This issue is fixed in version 2026.8.