CVE-2026-42346

medium

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.

References

https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-f7jj-p389-4w45

https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.7

https://github.com/gitroomhq/postiz-app/commit/071143dcb01cdeb9d5d7019892f4c6ff7b19dbeb

Details

Source: Mitre, NVD

Published: 2026-05-08

Updated: 2026-05-08

Risk Information

CVSS v2

Base Score: 6.1

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 6.5

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N

Severity: Medium