CVE-2026-46609: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in umbraco Umbraco-CMS
Umbraco is an ASP.NET CMS. From version 14.0.0 to before version 17.4.0, authenticated users are able to inject HTML into an input field, which is rendered in the confirmation dialog without proper output encoding. This issue has been patched in version 17.4.0.
AI Analysis
Technical Summary
CVE-2026-46609 is a CWE-79 (Improper Neutralization of Input During Web Page Generation) vulnerability affecting Umbraco-CMS, an ASP.NET content management system. From versions 14.0.0 through 17.3.x, authenticated users can inject HTML into an input field that is subsequently rendered in a confirmation dialog without adequate output encoding, enabling cross-site scripting attacks. The issue is resolved in version 17.4.0.
Potential Impact
The vulnerability allows authenticated users to perform reflected cross-site scripting attacks by injecting HTML content that is rendered without proper encoding. This can lead to limited confidentiality and integrity impacts, such as executing malicious scripts in the context of the affected user. The CVSS score is 4.6 (medium severity), indicating a moderate impact with network attack vector, low attack complexity, requiring privileges and user interaction, and limited confidentiality and integrity impact without availability impact.
Mitigation Recommendations
Upgrade Umbraco-CMS to version 17.4.0 or later, where this vulnerability has been patched. No other official remediation or temporary fixes are indicated. Until upgrading, restrict authenticated user privileges as appropriate to reduce risk.
CVE-2026-46609: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in umbraco Umbraco-CMS
Description
Umbraco is an ASP.NET CMS. From version 14.0.0 to before version 17.4.0, authenticated users are able to inject HTML into an input field, which is rendered in the confirmation dialog without proper output encoding. This issue has been patched in version 17.4.0.
CVSS v3.1
Score 4.6medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-46609 is a CWE-79 (Improper Neutralization of Input During Web Page Generation) vulnerability affecting Umbraco-CMS, an ASP.NET content management system. From versions 14.0.0 through 17.3.x, authenticated users can inject HTML into an input field that is subsequently rendered in a confirmation dialog without adequate output encoding, enabling cross-site scripting attacks. The issue is resolved in version 17.4.0.
Potential Impact
The vulnerability allows authenticated users to perform reflected cross-site scripting attacks by injecting HTML content that is rendered without proper encoding. This can lead to limited confidentiality and integrity impacts, such as executing malicious scripts in the context of the affected user. The CVSS score is 4.6 (medium severity), indicating a moderate impact with network attack vector, low attack complexity, requiring privileges and user interaction, and limited confidentiality and integrity impact without availability impact.
Mitigation Recommendations
Upgrade Umbraco-CMS to version 17.4.0 or later, where this vulnerability has been patched. No other official remediation or temporary fixes are indicated. Until upgrading, restrict authenticated user privileges as appropriate to reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-15T19:34:14.011Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a2998e3c9170919df3e8ed8
Added to database: 6/10/2026, 5:03:31 PM
Last enriched: 6/10/2026, 5:10:24 PM
Last updated: 6/10/2026, 6:16:02 PM
Views: 9
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