CVE-2026-42346: Gitroomhq Postiz-App

Medium severity, CVSS 6.5. EPSS: 0.4% chance of exploitation in the next 30 days.

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.

Affected products

• Gitroomhq Postiz-App: from 2.16.6, before 2.21.7 (fixed in 2.21.7)

Published 2026-05-08. Last modified 2026-07-24.