Description
Postiz is an AI social media scheduling tool. From version 2.16.6 to before version 2.21.7, all SSRF protections added in v2.21.4–v2.21.6 share a fundamental TOCTOU (Time-of-Check-Time-of-Use) vulnerability: isSafePublicHttpsUrl() resolves DNS to validate the target IP, but subsequent fetch() calls resolve DNS independently. An attacker controlling a DNS server can exploit this gap via DNS rebinding to redirect requests to internal network addresses. This issue has been patched in version 2.21.7.
Problem types
CWE-918: Server-Side Request Forgery (SSRF)
Product status
References
github.com/...iz-app/security/advisories/GHSA-f7jj-p389-4w45
github.com/...ommit/071143dcb01cdeb9d5d7019892f4c6ff7b19dbeb
github.com/gitroomhq/postiz-app/releases/tag/v2.21.7