CVE-2026-109345: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in cure53 DOMPurify
Description
DOMPurify versions before 3.4.16 contain a cross-site scripting (XSS) vulnerability. This flaw arises because the IN_PLACE mode returns a forcibly removed style element whose text content still includes markup. An attacker can exploit this by supplying a crafted style element containing a closing style tag and an img onerror payload, which executes script when the application serializes and re-parses the node.
CVSS v4.0
Score 5.1medium
Affected software
cure53
DOMPurify
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-109345 is a cross-site scripting vulnerability in DOMPurify before version 3.4.16. The vulnerability occurs due to improper neutralization of input during web page generation. Specifically, in IN_PLACE mode, a forcibly removed style element's text content retains markup, allowing attackers to inject a style element with a closing style tag and an img onerror attribute payload. This payload executes arbitrary script when the application serializes and re-parses the returned node, bypassing the sanitization process.
Potential Impact
Successful exploitation allows an attacker to execute arbitrary scripts in the context of the vulnerable web application, potentially leading to session hijacking, defacement, or other malicious actions that rely on script execution. The CVSS 4.0 score of 5.1 indicates a medium severity with network attack vector, low attack complexity, no privileges required, and user interaction needed.
Mitigation Recommendations
A fix is available in DOMPurify version 3.4.16. Users should upgrade to version 3.4.16 or later to remediate this vulnerability. No additional mitigation steps are indicated beyond applying the official patch.
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: 6acd0c162cdf04f656b11c06
Added to database: 10/12/2026, 16:34:30 UTC
Last enriched: 10/12/2026, 16:49:21 UTC
Last updated: 10/12/2026, 21:46:40 UTC
Views: 10
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