CVE-2026-42556

HIGH

Postiz stored XSS in public preview page

Title source: cna
STIX 2.1

Description

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.

References (2)

Core 2
Core References

Scores

CVSS v3 8.9
EPSS 0.0026
EPSS Percentile 16.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-79
Status published
Products (2)
gitroom/postiz 2.21.6
gitroomhq/postiz-app >= 2.21.6, < 2.21.7
Published May 08, 2026
Tracked Since May 09, 2026