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
The vulnerability in OpenProject (CVE-2026-44696) arises from the use of Sanitize::Config::RELAXED[:css] for inline style sanitization in the markdown rendering pipeline before version 17.4.0. This configuration allows nearly all CSS properties in style attributes on certain HTML elements, enabling authenticated users with write permissions to inject arbitrary CSS. Such injection constitutes a form of cross-site scripting (CWE-79) that can affect the integrity of the web interface. The issue is resolved in OpenProject 17.4.0.
Potential Impact
The vulnerability allows authenticated users with write access to inject arbitrary CSS into formattable text fields, which can lead to integrity violations such as UI manipulation or visual spoofing. The CVSS score of 5.7 (medium severity) reflects that the impact is on integrity without direct confidentiality or availability impact. There are no known exploits in the wild.
Mitigation Recommendations
Upgrade OpenProject to version 17.4.0 or later, where this vulnerability is fixed. Since this is a self-hosted product, administrators should apply the official update to remediate the issue. No alternative mitigations are specified.
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
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in OpenProject (CVE-2026-44696) arises from the use of Sanitize::Config::RELAXED[:css] for inline style sanitization in the markdown rendering pipeline before version 17.4.0. This configuration allows nearly all CSS properties in style attributes on certain HTML elements, enabling authenticated users with write permissions to inject arbitrary CSS. Such injection constitutes a form of cross-site scripting (CWE-79) that can affect the integrity of the web interface. The issue is resolved in OpenProject 17.4.0.
Potential Impact
The vulnerability allows authenticated users with write access to inject arbitrary CSS into formattable text fields, which can lead to integrity violations such as UI manipulation or visual spoofing. The CVSS score of 5.7 (medium severity) reflects that the impact is on integrity without direct confidentiality or availability impact. There are no known exploits in the wild.
Mitigation Recommendations
Upgrade OpenProject to version 17.4.0 or later, where this vulnerability is fixed. Since this is a self-hosted product, administrators should apply the official update to remediate the issue. No alternative mitigations are specified.
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: 07/03/2026, 22:35:10 UTC
Last updated: 08/10/2026, 12:41:11 UTC
Views: 49
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
External Links
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.