CVE-2026-42556

EUVD-2026-28866

08.05.2026, 23:16

Postiz is an AI social media scheduling tool. From version 2.21.6 to before version 2.21.7, any authenticated user who can create a post can store arbitrary HTML in post content by tampering their own save request and send the public preview link /p/<postId>?share=true to another user. The preview page renders that stored HTML with dangerouslySetInnerHTML on the main application origin. This issue has been patched in version 2.21.7.

Cross-site Scripting

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	Primary	8.9 HIGH	NETWORK	LOW	LOW	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L

Base Score

CVSS 3.x

EPSS Score

Percentile: 16%

Affected Products (NVD)

Vendor	Product	Version
gitroom	postiz	2.21.6

𝑥

= Vulnerable software versions

Common Weakness Enumeration

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

References

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

https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-hhxq-3wg7-4rj8