CVE-2026-75838: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in cure53 DOMPurify
DOMPurify versions before 3.4.13 contain a cross-site scripting (XSS) vulnerability in the IN_PLACE sanitization method. The vulnerability arises because element-removal hooks fail to neutralize detached subtrees, allowing attackers to inject HTML with event handlers on descendant elements that execute after sanitization. This occurs even though the returned root element appears clean after sanitization.
AI Analysis
Technical Summary
CVE-2026-75838 is a cross-site scripting vulnerability in DOMPurify prior to version 3.4.13. The flaw exists in the IN_PLACE sanitization process where element-removal hooks do not properly neutralize detached subtrees. As a result, malicious HTML containing event handlers on descendant elements can execute after the sanitization completes, bypassing the intended cleaning mechanism. This allows attackers to execute scripts in the context of the sanitized page.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary scripts in the context of a web page that uses the affected versions of DOMPurify for sanitization. This could lead to typical XSS impacts such as session hijacking, defacement, or redirection to malicious sites. The CVSS score of 5.1 indicates a medium severity level, reflecting that the attack requires network access, low complexity, and user interaction but no privileges or authentication.
Mitigation Recommendations
A fix is available in DOMPurify version 3.4.13. Users should upgrade to version 3.4.13 or later to remediate this vulnerability. No other mitigation actions are indicated by the vendor advisory.
CVE-2026-75838: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in cure53 DOMPurify
Description
DOMPurify versions before 3.4.13 contain a cross-site scripting (XSS) vulnerability in the IN_PLACE sanitization method. The vulnerability arises because element-removal hooks fail to neutralize detached subtrees, allowing attackers to inject HTML with event handlers on descendant elements that execute after sanitization. This occurs even though the returned root element appears clean after sanitization.
CVSS v4.0
Score 5.1medium
Affected software
cure53
DOMPurify
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-75838 is a cross-site scripting vulnerability in DOMPurify prior to version 3.4.13. The flaw exists in the IN_PLACE sanitization process where element-removal hooks do not properly neutralize detached subtrees. As a result, malicious HTML containing event handlers on descendant elements can execute after the sanitization completes, bypassing the intended cleaning mechanism. This allows attackers to execute scripts in the context of the sanitized page.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary scripts in the context of a web page that uses the affected versions of DOMPurify for sanitization. This could lead to typical XSS impacts such as session hijacking, defacement, or redirection to malicious sites. The CVSS score of 5.1 indicates a medium severity level, reflecting that the attack requires network access, low complexity, and user interaction but no privileges or authentication.
Mitigation Recommendations
A fix is available in DOMPurify version 3.4.13. Users should upgrade to version 3.4.13 or later to remediate this vulnerability. No other mitigation actions are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-08-18T10:59:33.701Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a844367c6e8be0332229748
Added to database: 08/18/2026, 11:35:03 UTC
Last enriched: 09/11/2026, 23:06:05 UTC
Last updated: 10/02/2026, 02:46:06 UTC
Views: 69
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