CVE-2026-41239: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in cure53 DOMPurify
CVE-2026-41239 is a cross-site scripting (XSS) vulnerability in DOMPurify versions from 1. 0. 10 up to but not including 3. 4. 0. The issue arises because the SAFE_FOR_TEMPLATES option strips {{... }} expressions only in string mode but fails to do so when using RETURN_DOM or RETURN_DOM_FRAGMENT modes. This allows XSS attacks in template-evaluating frameworks such as Vue 2. The vulnerability is addressed in version 3. 4.
AI Analysis
Technical Summary
DOMPurify is a sanitizer designed to prevent XSS by cleaning HTML, MathML, and SVG content. Versions >=1.0.10 and <3.4.0 have a flaw in the SAFE_FOR_TEMPLATES feature: it removes template expressions ({{...}}) only when sanitizing strings, but not when returning DOM nodes or fragments. This inconsistency permits injection of malicious scripts in frameworks that evaluate templates, enabling cross-site scripting attacks. The issue is fixed in version 3.4.0.
Potential Impact
Successful exploitation can lead to high impact on confidentiality and integrity by executing arbitrary scripts in the context of the vulnerable web application. This can result in theft of sensitive information or session hijacking. The CVSS score is 6.8 (medium severity), reflecting network attack vector, high complexity, no privileges required, user interaction needed, and high impact on confidentiality and integrity.
Mitigation Recommendations
Upgrade DOMPurify to version 3.4.0 or later, where this vulnerability is patched. No other official remediation or temporary fixes are documented. Patch status is not explicitly stated in the vendor advisory, but the description confirms version 3.4.0 addresses the issue.
CVE-2026-41239: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in cure53 DOMPurify
Description
CVE-2026-41239 is a cross-site scripting (XSS) vulnerability in DOMPurify versions from 1. 0. 10 up to but not including 3. 4. 0. The issue arises because the SAFE_FOR_TEMPLATES option strips {{... }} expressions only in string mode but fails to do so when using RETURN_DOM or RETURN_DOM_FRAGMENT modes. This allows XSS attacks in template-evaluating frameworks such as Vue 2. The vulnerability is addressed in version 3. 4.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
DOMPurify is a sanitizer designed to prevent XSS by cleaning HTML, MathML, and SVG content. Versions >=1.0.10 and <3.4.0 have a flaw in the SAFE_FOR_TEMPLATES feature: it removes template expressions ({{...}}) only when sanitizing strings, but not when returning DOM nodes or fragments. This inconsistency permits injection of malicious scripts in frameworks that evaluate templates, enabling cross-site scripting attacks. The issue is fixed in version 3.4.0.
Potential Impact
Successful exploitation can lead to high impact on confidentiality and integrity by executing arbitrary scripts in the context of the vulnerable web application. This can result in theft of sensitive information or session hijacking. The CVSS score is 6.8 (medium severity), reflecting network attack vector, high complexity, no privileges required, user interaction needed, and high impact on confidentiality and integrity.
Mitigation Recommendations
Upgrade DOMPurify to version 3.4.0 or later, where this vulnerability is patched. No other official remediation or temporary fixes are documented. Patch status is not explicitly stated in the vendor advisory, but the description confirms version 3.4.0 addresses the issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-18T03:47:03.135Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69ea9e7b87115cfb686fc58b
Added to database: 4/23/2026, 10:34:35 PM
Last enriched: 4/23/2026, 10:36:11 PM
Last updated: 4/24/2026, 7:18:38 AM
Views: 5
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