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Vulnerability record · CVE-2026-42556 · published 8 May 2026

CVE-2026-42556: Gitroom postiz cross-site scripting vulnerability

Gitroom · Postiz

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.

9.0 CVSS 3.1 Critical EPSS 0.44% · top 64.5% CWE-79 · Cross-site scripting
9.0CVSS 3.1 base score
0.44%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
24 Jul 2026Last modified by NVD

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.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/gitroomhq/postiz-app/releases/tag/v2.21.7 ProductRelease Notes
https://github.com/gitroomhq/postiz-app/security/advisories/GHSA-hhxq-3wg7-4rj8 Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-42556), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.