XML‑RPC login leak exposes valid session ID enabling unauthorized API access

Summary

HackerOne community member Kenji Subagja (garuthacktivist) has reported a way to bypass the admin‑only restriction of the XML‑RPC API in Revive Adserver 6.0.7. The API response for the ox.login method returned a session ID cookie in the HTTP headers, and although the method correctly returned an error, the associated session was not invalidated. As a result, the leaked session ID could be used to perform subsequent API calls without restrictions.