CVE-2026-42556: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in gitroomhq postiz-app
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.
AI Analysis
Technical Summary
The vulnerability in postiz-app (versions >= 2.21.6 and < 2.21.7) allows authenticated users with post creation privileges to store arbitrary HTML in post content by manipulating their save request. The stored HTML is rendered on the public preview page (/p/<postId>?share=true) using dangerouslySetInnerHTML, which does not sanitize the input, leading to a cross-site scripting (CWE-79) vulnerability. This can result in a complete compromise of confidentiality and integrity (CVSS 8.9) with limited availability impact. The vulnerability was patched in version 2.21.7.
Potential Impact
Successful exploitation allows an attacker to execute arbitrary HTML/JavaScript in the context of the postiz-app origin when a user views the public preview link. This can lead to theft of sensitive information, session hijacking, or other high-impact consequences affecting confidentiality and integrity. The availability impact is low. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade postiz-app to version 2.21.7 or later, where this vulnerability has been patched. Since this is a self-hosted application, applying the official fix is necessary to remediate the issue. Patch status is confirmed by the vendor's versioning information. No additional mitigations are specified.
CVE-2026-42556: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in gitroomhq postiz-app
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in postiz-app (versions >= 2.21.6 and < 2.21.7) allows authenticated users with post creation privileges to store arbitrary HTML in post content by manipulating their save request. The stored HTML is rendered on the public preview page (/p/<postId>?share=true) using dangerouslySetInnerHTML, which does not sanitize the input, leading to a cross-site scripting (CWE-79) vulnerability. This can result in a complete compromise of confidentiality and integrity (CVSS 8.9) with limited availability impact. The vulnerability was patched in version 2.21.7.
Potential Impact
Successful exploitation allows an attacker to execute arbitrary HTML/JavaScript in the context of the postiz-app origin when a user views the public preview link. This can lead to theft of sensitive information, session hijacking, or other high-impact consequences affecting confidentiality and integrity. The availability impact is low. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade postiz-app to version 2.21.7 or later, where this vulnerability has been patched. Since this is a self-hosted application, applying the official fix is necessary to remediate the issue. Patch status is confirmed by the vendor's versioning information. No additional mitigations are specified.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-28T16:56:50.192Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69fe68edcbff5d861039d886
Added to database: 5/8/2026, 10:51:25 PM
Last enriched: 5/8/2026, 11:06:44 PM
Last updated: 5/9/2026, 2:41:44 AM
Views: 7
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