Arbitrary HTML Injection in Postiz AI Social Media Tool
CVE-2026-42556

8.9HIGH

Key Information:

Vendor

Gitroomhq

Status
Postiz-app
Vendor
CVE Published:
8 May 2026

What is CVE-2026-42556?

The Postiz AI social media scheduling tool contains a vulnerability that allows authenticated users to store arbitrary HTML content in posts. By manipulating the save request during post creation, users can render this HTML on the public preview link. The stored HTML is displayed using dangerouslySetInnerHTML, which poses significant security risks. This flaw has been addressed in version 2.21.7, emphasizing the importance of upgrading to this version to mitigate any potential exploitation.

Affected Version(s)

postiz-app >= 2.21.6, < 2.21.7

References

https://github.com/gitroomhq/postiz-app/security/advisori...
x_refsource_CONFIRM
https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.7
x_refsource_MISC

CVSS V3.1

Score:
8.9
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
Required
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.