CVE-2026-44696: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in opf openproject
OpenProject is open-source, web-based project management software. Prior to 17.4.0, OpenProject's rich text (markdown) rendering pipeline uses Sanitize::Config::RELAXED[:css] for inline style sanitization. This configuration permits essentially all CSS properties in style attributes on permitted HTML elements (figure, img, table, th, tr, td). This allows any authenticated user with write access to formattable text fields (work package descriptions, comments, project descriptions, news) to inject CSS This vulnerability is fixed in 17.4.0.
AI Analysis
Technical Summary
OpenProject's rich text markdown rendering pipeline used Sanitize::Config::RELAXED[:css] for inline style sanitization before version 17.4.0. This configuration permitted nearly all CSS properties in style attributes on certain HTML elements, enabling authenticated users with write access to inject arbitrary CSS. This constitutes a cross-site scripting (CWE-79) vulnerability. The vulnerability is resolved in OpenProject 17.4.0.
Potential Impact
The vulnerability allows an authenticated user with write permissions to inject arbitrary CSS into formattable text fields. This can lead to cross-site scripting impacts, specifically integrity impacts (as indicated by the CVSS vector), but does not affect confidentiality or availability. The CVSS score is 5.7 (medium severity). There are no known exploits in the wild.
Mitigation Recommendations
This vulnerability is fixed in OpenProject version 17.4.0. Users should upgrade to version 17.4.0 or later to remediate this issue. No other official remediation or temporary fixes are indicated. Patch status is confirmed by the vendor advisory stating the fix is included in 17.4.0.
CVE-2026-44696: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in opf openproject
Description
OpenProject is open-source, web-based project management software. Prior to 17.4.0, OpenProject's rich text (markdown) rendering pipeline uses Sanitize::Config::RELAXED[:css] for inline style sanitization. This configuration permits essentially all CSS properties in style attributes on permitted HTML elements (figure, img, table, th, tr, td). This allows any authenticated user with write access to formattable text fields (work package descriptions, comments, project descriptions, news) to inject CSS This vulnerability is fixed in 17.4.0.
CVSS v3.1
Score 5.7medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
OpenProject's rich text markdown rendering pipeline used Sanitize::Config::RELAXED[:css] for inline style sanitization before version 17.4.0. This configuration permitted nearly all CSS properties in style attributes on certain HTML elements, enabling authenticated users with write access to inject arbitrary CSS. This constitutes a cross-site scripting (CWE-79) vulnerability. The vulnerability is resolved in OpenProject 17.4.0.
Potential Impact
The vulnerability allows an authenticated user with write permissions to inject arbitrary CSS into formattable text fields. This can lead to cross-site scripting impacts, specifically integrity impacts (as indicated by the CVSS vector), but does not affect confidentiality or availability. The CVSS score is 5.7 (medium severity). There are no known exploits in the wild.
Mitigation Recommendations
This vulnerability is fixed in OpenProject version 17.4.0. Users should upgrade to version 17.4.0 or later to remediate this issue. No other official remediation or temporary fixes are indicated. Patch status is confirmed by the vendor advisory stating the fix is included in 17.4.0.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-07T17:07:09.316Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a3edc0372d29f1837f46498
Added to database: 06/26/2026, 20:07:31 UTC
Last enriched: 06/26/2026, 20:12:58 UTC
Last updated: 06/26/2026, 20:36:39 UTC
Views: 6
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