CVE-2026-66010

MEDIUMPre-NVD 6.16.1—
EchelonGraph scoreMEDIUM confidence

Score 6.1 from GitHub Security Advisory published 2026-07-24. a secondary CVSS source baseline 6.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this weekElevated
6.1EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.1Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
6.1
EG Score
6.1(medium)
EG Risk
43(Track)
EG Risk 43/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity61% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
12%
KEV
Not listed

Published

July 24, 2026

Last Modified

August 6, 2026

Advisory Details (2)

Auto-updated Jul 24, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

`CUSTOM_ELEMENT_HANDLING` bypasses `afterSanitizeElements` for allowed custom elements. · Advisory · cure53/DOMPurify · GitHub

https://github.com/cure53/DOMPurify/security/advisories/GHSA-c2j3-45gr-mqc4
generic

DOMPurify before 3.4.12 Hook Bypass via CUSTOM_ELEMENT_HANDLING | Advisories | VulnCheck

https://www.vulncheck.com/advisories/dompurify-before-hook-bypass-via-custom-element-handling

Vendor Advisories for CVE-2026-66010(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(4 across 4 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
node-dompurify2.4.1+dfsg+~2.4.0-1 ... 3.4.5+dfsg-1 (15 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
node-dompurify3.1.7+dfsg+~3.0.5-2 ... 3.4.5+dfsg-1 (9 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
node-dompurify3.1.7+dfsg+~3.0.5-2 ... 3.4.5+dfsg-1 (8 versions)3.4.12+dfsg-1—
npm(1)
PackageVulnerable rangeFixed inDependents
dompurify—3.4.12—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 19× in last 7d / 83× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-26 08:40 UTCEG score recompute
  2. 2026-08-26 08:40 UTCGHSA enrichment
  3. 2026-08-25 13:49 UTCEPSS rescore
  4. 2026-08-25 07:03 UTCEG score recompute
  5. 2026-08-25 07:03 UTCGHSA enrichment
  6. 2026-08-24 05:31 UTCEG score recompute
  7. 2026-08-24 05:31 UTCGHSA enrichment
  8. 2026-08-23 04:00 UTCEG score recompute
  9. 2026-08-23 03:59 UTCGHSA enrichment
  10. 2026-08-23 00:19 UTCEPSS rescore
  11. 2026-08-22 02:28 UTCEG score recompute
  12. 2026-08-22 02:28 UTCGHSA enrichment
  13. 2026-08-21 23:49 UTCEPSS rescore
  14. 2026-08-21 00:56 UTCEG score recompute
  15. 2026-08-21 00:56 UTCGHSA enrichment
  16. 2026-08-20 22:56 UTCEPSS rescore
  17. 2026-08-19 23:25 UTCEG score recompute
  18. 2026-08-19 23:25 UTCGHSA enrichment
  19. 2026-08-19 17:04 UTCEPSS rescore
  20. 2026-08-18 21:54 UTCEG score recompute
  21. 2026-08-18 21:54 UTCGHSA enrichment
  22. 2026-08-18 13:48 UTCEPSS rescore
  23. 2026-08-17 20:22 UTCEG score recompute
  24. 2026-08-17 20:22 UTCGHSA enrichment
  25. 2026-08-17 13:47 UTCEPSS rescore
Show 68 more
  1. 2026-08-16 16:07 UTCEG score recompute
  2. 2026-08-16 16:07 UTCGHSA enrichment
  3. 2026-08-16 14:56 UTCEPSS rescore
  4. 2026-08-15 14:36 UTCEG score recompute
  5. 2026-08-15 14:36 UTCGHSA enrichment
  6. 2026-08-15 01:30 UTCEPSS rescore
  7. 2026-08-14 13:05 UTCEG score recompute
  8. 2026-08-14 13:05 UTCGHSA enrichment
  9. 2026-08-13 22:00 UTCEPSS rescore
  10. 2026-08-13 11:33 UTCEG score recompute
  11. 2026-08-13 11:33 UTCGHSA enrichment
  12. 2026-08-12 13:51 UTCEPSS rescore
  13. 2026-08-12 10:02 UTCEG score recompute
  14. 2026-08-12 10:02 UTCGHSA enrichment
  15. 2026-08-11 08:31 UTCEG score recompute
  16. 2026-08-11 08:31 UTCGHSA enrichment
  17. 2026-08-11 00:00 UTCEPSS rescore
  18. 2026-08-10 06:59 UTCEG score recompute
  19. 2026-08-10 06:59 UTCGHSA enrichment
  20. 2026-08-09 13:47 UTCEPSS rescore
  21. 2026-08-09 05:28 UTCEG score recompute
  22. 2026-08-09 05:28 UTCGHSA enrichment
  23. 2026-08-08 16:37 UTCEPSS rescore
  24. 2026-08-08 03:57 UTCEG score recompute
  25. 2026-08-08 03:57 UTCGHSA enrichment
  26. 2026-08-07 02:26 UTCEG score recompute
  27. 2026-08-07 02:26 UTCGHSA enrichment
  28. 2026-08-06 13:47 UTCEPSS rescore
  29. 2026-08-06 00:55 UTCEG score recompute
  30. 2026-08-06 00:55 UTCGHSA enrichment
  31. 2026-08-05 19:17 UTCEPSS rescore
  32. 2026-08-05 19:17 UTCEPSS rescore
  33. 2026-08-05 03:55 UTCEG score recompute
  34. 2026-08-05 03:55 UTCGHSA enrichment
  35. 2026-08-04 15:10 UTCEPSS rescore
  36. 2026-08-04 10:39 UTCEPSS rescore
  37. 2026-08-04 02:24 UTCEG score recompute
  38. 2026-08-04 02:24 UTCGHSA enrichment
  39. 2026-08-03 10:36 UTCEPSS rescore
  40. 2026-08-03 00:53 UTCEG score recompute
  41. 2026-08-03 00:53 UTCGHSA enrichment
  42. 2026-08-02 02:27 UTCEPSS rescore
  43. 2026-08-01 23:22 UTCEG score recompute
  44. 2026-08-01 23:22 UTCGHSA enrichment
  45. 2026-08-01 04:16 UTCEPSS rescore
  46. 2026-07-31 21:50 UTCGHSA enrichment
  47. 2026-07-30 20:14 UTCEG score recompute
  48. 2026-07-30 20:14 UTCGHSA enrichment
  49. 2026-07-30 16:28 UTCEPSS rescore
  50. 2026-07-30 09:15 UTCEG score recompute
  51. 2026-07-30 09:15 UTCGHSA enrichment
  52. 2026-07-30 01:30 UTCEPSS rescore
  53. 2026-07-29 07:44 UTCEG score recompute
  54. 2026-07-29 07:44 UTCGHSA enrichment
  55. 2026-07-28 15:37 UTCEPSS rescore
  56. 2026-07-28 06:09 UTCEG score recompute
  57. 2026-07-28 06:09 UTCGHSA enrichment
  58. 2026-07-27 14:14 UTCEPSS rescore
  59. 2026-07-27 04:38 UTCEG score recompute
  60. 2026-07-27 04:37 UTCGHSA enrichment
  61. 2026-07-26 14:54 UTCEPSS rescore
  62. 2026-07-26 14:54 UTCEPSS rescore
  63. 2026-07-26 03:03 UTCEG score recompute
  64. 2026-07-26 03:03 UTCGHSA enrichment
  65. 2026-07-25 14:18 UTCEPSS rescore
  66. 2026-07-25 14:18 UTCEPSS rescore
  67. 2026-07-24 12:42 UTCEG score recompute
  68. 2026-07-24 12:41 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-66010?
CVE-2026-66010 is a medium vulnerability published on July 24, 2026. DOMPurify before 3.4.12 fails to execute afterSanitizeElements hook for custom elements allowed via CUSTOMELEMENTHANDLING.tagNameCheck, allowing attributes to bypass application security policies. Attackers can preserve sensitive attributes on custom elements that later re-inject them into…
When was CVE-2026-66010 disclosed?
CVE-2026-66010 was first published in the National Vulnerability Database on July 24, 2026, with the most recent update on August 6, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-66010 actively exploited?
CVE-2026-66010 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 88.3% of all scored CVEs.
What is the CVSS score of CVE-2026-66010?
CVE-2026-66010 has a CVSS v3 base score of 6.1 (NVD).
How do I remediate CVE-2026-66010?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-66010, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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