CVE-2026-34577 — Postiz: Unauthenticated Full-Read SSRF via /public/stream Endpoint with Trivially Bypassable Extension Check
Postiz is an AI social media scheduling tool. Prior to version 2.21.3, the GET /public/stream endpoint in PublicController accepts a user-supplied url query parameter and proxie…
Published: 2026-04-02 · CVSS: 8.6 · CVSS 3.1
Postiz is an AI social media scheduling tool. Prior to version 2.21.3, the GET /public/stream endpoint in PublicController accepts a user-supplied url query parameter and proxies the full HTTP response back to the caller. The only validation is url.endsWith('mp4'), which is trivially bypassable by appending .mp4 as a query parameter value or URL fragment. The endpoint requires no authentication and has no SSRF protections, allowing an unauthenticated attacker to read responses from internal services, cloud metadata endpoints, and other network-internal resources. This issue has been patched in version 2.21.3.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7