CVE-2026-66010 (GCVE-0-2026-66010)

Vulnerability from cvelistv5 – Published: 2026-07-24 12:07 – Updated: 2026-09-17 17:54
VLAI
Title
DOMPurify before 3.4.12 Hook Bypass via CUSTOM_ELEMENT_HANDLING
Summary
DOMPurify before 3.4.12 fails to execute afterSanitizeElements hook for custom elements allowed via CUSTOM_ELEMENT_HANDLING.tagNameCheck, allowing attributes to bypass application security policies. Attackers can preserve sensitive attributes on custom elements that later re-inject them into innerHTML sinks, creating second-order XSS gadgets.
Severity
5.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-24 14:13 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version CPE status
cure53 DOMPurify Affected: 0 , < 3.4.12 (semver)
Unaffected: 3.4.12 (semver)
    cpe:2.3:a:cure53:dompurify:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-11 00:00
Credits
Rikuxx0
Show details on NVD website
To clipboard 

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