CVE-2021-30551

CRITICALNVD 8.89.0
EchelonGraph scoreHIGH confidence

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 8.8 retained for reference. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, epss, ghsa, nvd
Trending — 5 sources updated this weekExploited in the wild
9.0EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS PROB: 65%CVSS: 8.8Exploit: cisa kev · ssvc active · epss top5pct · epss high · public exploitExposed: 0

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

Type confusion in V8 in Google Chrome prior to 91.0.4472.101 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.

CVSS v3
8.8
EG Score
9.0(high)
EG Risk
81(Attend)
EG Risk 81/100SSVC: Attend

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
Severity90% × 45%
Exploitation100% × 40%
Automatability0% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
65%
EPSS %ILE
99%
KEV
⚠ Exploited

Published

June 15, 2021

Last Modified

October 24, 2025

Advisory Details (6)

Auto-updated Jun 2, 2026
⚠️ Active exploitation confirmed. No patch confirmed yet.
generic

[SECURITY] Fedora 34 Update: chromium-91.0.4472.114-1.fc34 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PAT6EOXVQFE6JFMFQF4IKAOUQSHMHL54/
generic

[SECURITY] Fedora 33 Update: chromium-91.0.4472.114-2.fc33 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ETMZL6IHCTCTREEL434BQ4THQ7EOHJ43/
generic🔴 Active Exploitation

Chrome Releases: Stable Channel Update for Desktop

https://chromereleases.googleblog.com/2021/06/stable-channel-update-for-desktop.html
generic

Chromium, Google Chrome, Microsoft Edge, QtWebEngine: Multiple Vulnerabilities (GLSA 202208-25) — Gentoo security

https://security.gentoo.org/glsa/202208-25
generic

Chromium, Google Chrome: Multiple vulnerabilities (GLSA 202107-06) — Gentoo security

https://security.gentoo.org/glsa/202107-06

Weakness Classification(1)

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

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 61× in last 7d / 341× 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.

Showing the most recent 100 of 679 total refreshes for this CVE.

  1. 2026-07-27 21:39 UTCVendor advisory
  2. 2026-07-27 21:39 UTCGHSA enrichment
  3. 2026-07-27 19:24 UTCCISA KEV update
  4. 2026-07-27 17:18 UTCVendor advisory
  5. 2026-07-27 17:18 UTCGHSA enrichment
  6. 2026-07-27 17:17 UTCCISA KEV update
  7. 2026-07-27 12:57 UTCVendor advisory
  8. 2026-07-27 12:57 UTCGHSA enrichment
  9. 2026-07-27 08:36 UTCVendor advisory
  10. 2026-07-27 08:36 UTCGHSA enrichment
  11. 2026-07-27 04:16 UTCVendor advisory
  12. 2026-07-27 04:16 UTCGHSA enrichment
  13. 2026-07-26 23:55 UTCVendor advisory
  14. 2026-07-26 23:54 UTCGHSA enrichment
  15. 2026-07-26 19:34 UTCVendor advisory
  16. 2026-07-26 19:33 UTCGHSA enrichment
  17. 2026-07-26 15:12 UTCEG score recompute
  18. 2026-07-26 15:12 UTCVendor advisory
  19. 2026-07-26 15:12 UTCGHSA enrichment
  20. 2026-07-26 14:52 UTCEPSS rescore
  21. 2026-07-26 14:52 UTCEPSS rescore
  22. 2026-07-26 10:50 UTCEG score recompute
  23. 2026-07-26 10:50 UTCVendor advisory
  24. 2026-07-26 10:50 UTCGHSA enrichment
  25. 2026-07-26 06:30 UTCVendor advisory
Show 75 more
  1. 2026-07-26 06:30 UTCGHSA enrichment
  2. 2026-07-26 02:09 UTCEG score recompute
  3. 2026-07-26 02:09 UTCVendor advisory
  4. 2026-07-26 02:09 UTCGHSA enrichment
  5. 2026-07-25 14:15 UTCEPSS rescore
  6. 2026-07-24 14:15 UTCEPSS rescore
  7. 2026-07-23 02:00 UTCEG score recompute
  8. 2026-07-22 22:29 UTCEG score recompute
  9. 2026-07-22 22:29 UTCVendor advisory
  10. 2026-07-22 22:29 UTCGHSA enrichment
  11. 2026-07-22 19:40 UTCCISA KEV update
  12. 2026-07-22 18:07 UTCEG score recompute
  13. 2026-07-22 18:06 UTCGHSA enrichment
  14. 2026-07-22 14:06 UTCEPSS rescore
  15. 2026-07-22 14:06 UTCEPSS rescore
  16. 2026-07-22 13:44 UTCGHSA enrichment
  17. 2026-07-22 09:22 UTCVendor advisory
  18. 2026-07-22 09:22 UTCGHSA enrichment
  19. 2026-07-22 05:01 UTCVendor advisory
  20. 2026-07-22 05:01 UTCGHSA enrichment
  21. 2026-07-22 00:40 UTCVendor advisory
  22. 2026-07-22 00:40 UTCGHSA enrichment
  23. 2026-07-21 20:18 UTCVendor advisory
  24. 2026-07-21 20:18 UTCGHSA enrichment
  25. 2026-07-21 15:56 UTCEG score recompute
  26. 2026-07-21 15:56 UTCVendor advisory
  27. 2026-07-21 15:56 UTCGHSA enrichment
  28. 2026-07-21 15:22 UTCEPSS rescore
  29. 2026-07-21 15:22 UTCEPSS rescore
  30. 2026-07-21 14:37 UTCCISA KEV update
  31. 2026-07-21 11:34 UTCVendor advisory
  32. 2026-07-21 11:34 UTCGHSA enrichment
  33. 2026-07-21 07:11 UTCVendor advisory
  34. 2026-07-21 07:11 UTCGHSA enrichment
  35. 2026-07-21 02:51 UTCVendor advisory
  36. 2026-07-21 02:50 UTCGHSA enrichment
  37. 2026-07-20 22:27 UTCVendor advisory
  38. 2026-07-20 22:27 UTCGHSA enrichment
  39. 2026-07-20 18:07 UTCEG score recompute
  40. 2026-07-20 18:07 UTCVendor advisory
  41. 2026-07-20 18:06 UTCGHSA enrichment
  42. 2026-07-20 17:05 UTCEPSS rescore
  43. 2026-07-20 13:44 UTCGHSA enrichment
  44. 2026-07-20 09:23 UTCVendor advisory
  45. 2026-07-20 09:23 UTCGHSA enrichment
  46. 2026-07-20 05:03 UTCVendor advisory
  47. 2026-07-20 05:02 UTCGHSA enrichment
  48. 2026-07-20 00:41 UTCVendor advisory
  49. 2026-07-19 20:20 UTCVendor advisory
  50. 2026-07-19 20:20 UTCGHSA enrichment
  51. 2026-07-19 15:57 UTCEG score recompute
  52. 2026-07-19 15:57 UTCVendor advisory
  53. 2026-07-19 15:57 UTCGHSA enrichment
  54. 2026-07-19 14:28 UTCEPSS rescore
  55. 2026-07-19 11:34 UTCVendor advisory
  56. 2026-07-19 11:34 UTCGHSA enrichment
  57. 2026-07-19 07:13 UTCVendor advisory
  58. 2026-07-19 07:13 UTCGHSA enrichment
  59. 2026-07-19 02:52 UTCVendor advisory
  60. 2026-07-19 02:52 UTCGHSA enrichment
  61. 2026-07-18 22:30 UTCVendor advisory
  62. 2026-07-18 22:30 UTCGHSA enrichment
  63. 2026-07-18 18:09 UTCVendor advisory
  64. 2026-07-18 18:09 UTCGHSA enrichment
  65. 2026-07-18 13:48 UTCVendor advisory
  66. 2026-07-18 13:48 UTCGHSA enrichment
  67. 2026-07-18 09:27 UTCVendor advisory
  68. 2026-07-18 09:27 UTCGHSA enrichment
  69. 2026-07-18 05:06 UTCVendor advisory
  70. 2026-07-18 05:05 UTCGHSA enrichment
  71. 2026-07-18 00:43 UTCVendor advisory
  72. 2026-07-18 00:43 UTCGHSA enrichment
  73. 2026-07-17 20:22 UTCVendor advisory
  74. 2026-07-17 20:22 UTCGHSA enrichment
  75. 2026-07-17 16:01 UTCVendor advisory

Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCxmzyshypnc/CVE-2021-30551
    First seen Aug 22, 2021

    my exp for chrome V8 CVE-2021-30551

    Open source ↗

Frequently asked(6)

What is CVE-2021-30551?
CVE-2021-30551 is a critical vulnerability published on June 15, 2021. Type confusion in V8 in Google Chrome prior to 91.0.4472.101 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.
When was CVE-2021-30551 disclosed?
CVE-2021-30551 was first published in the National Vulnerability Database on June 15, 2021, with the most recent update on October 24, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-30551 actively exploited?
Yes. CISA added CVE-2021-30551 to the Known Exploited Vulnerabilities catalog on November 3, 2021, affecting Google Chromium V8. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2021-30551?
CVE-2021-30551 has a CVSS v3 base score of 8.8 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0.
Which products are affected by CVE-2021-30551?
CVE-2021-30551 affects Google Chromium V8. The full affected-products list, including version ranges and fixed versions, is shown in the Affected Packages section of this page.
How do I remediate CVE-2021-30551?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-30551, 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

Explore the affected products and dependency analysis for CVE-2021-30551

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