CVE-2026-109344: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in cure53 DOMPurify
Description
DOMPurify versions 3.4.13 through 3.4.15 contain a cross-site scripting (XSS) vulnerability. The issue arises because the IN_PLACE mode does not properly neutralize subtrees detached by afterSanitizeElements or afterSanitizeAttributes hooks. This allows attackers to inject markup with event handlers that remain active on the live DOM, enabling script execution in the victim's origin.
CVSS v4.0
Score 5.1medium
Affected software
cure53
DOMPurify
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in DOMPurify from version 3.4.13 before 3.4.16 is due to improper neutralization of input during web page generation. Specifically, the IN_PLACE mode fails to sanitize subtrees detached by afterSanitizeElements or afterSanitizeAttributes hooks, allowing event handlers (on* attributes) inside removed wrappers to remain active on the live DOM. This results in a cross-site scripting (XSS) vulnerability where attacker-supplied scripts can execute in the context of the victim's origin.
Potential Impact
Successful exploitation can lead to cross-site scripting attacks, allowing attackers to execute arbitrary scripts in the victim's browser within the affected origin. This can lead to session hijacking, information disclosure, or other malicious actions within the context of the vulnerable web application.
Mitigation Recommendations
A fix is available in DOMPurify version 3.4.16 and later. Users should upgrade to version 3.4.16 or newer to remediate this vulnerability. No other mitigation guidance is provided by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-10-12T14:19:01.653Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6acd0c162cdf04f656b11c05
Added to database: 10/12/2026, 16:34:30 UTC
Last enriched: 10/12/2026, 16:49:24 UTC
Last updated: 10/12/2026, 21:46:41 UTC
Views: 9
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