CVE-2026-66010 — Security Box Score

CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-66010MEDIUM

cure53 DOMPurify — DOMPurify before 3.4.12 Hook Bypass via CUSTOM_ELEMENT_HANDLING

  AV  AC  AT  PR  UI  VC  VI  VA   CVSS    EPSS   %ile   KEV
   N   L   N   N   A   N   N   N    5.1   .0016    6.2     —

AFFECTED
  Product    Versions     Fixed
  DOMPurify  unspecified  3.4.12

TIMELINE
  Jul 23  Reserved by VulnCheck
  Jul 24  EXPLOIT PUBLISHED — CVE-2026-66010 (cure53 DOMPurify). Public exploit reference added.
  Jul 24  Published (CNA: VulnCheck)

CWE-79 · CNA: VulnCheck · CVSS v4.0 · 2 references · NVD status: Analyzed

Description

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
July 23, 2026	Reserved	Reserved by VulnCheck
July 24, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-66010 (cure53 DOMPurify). Public exploit reference added.
July 24, 2026	Published	Published (CNA: VulnCheck)

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
cure53	DOMPurify	—	—	3.4.12

Weaknesses

CWE-79

References (2)

https://github.com/cure53/DOMPurify/security/advisories/GHSA-c2j3-45gr-mqc4 [Exploit, Vendor Advisory]
https://www.vulncheck.com/advisories/dompurify-before-hook-bypass-via-custom-element-handling [Third Party Advisory]

Authoritative record: CVE-2026-66010 at cve.org

Vendors: cure53

Weaknesses: CWE-79

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-66010 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.