CVE-2021-30533

CRITICALNVD 6.59.0▲
EchelonGraph scoreHIGH confidence

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2022-06-27), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 6.5 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: 17%CVSS: 6.5Exploit: cisa kev · ssvc active · epss top5pctExposed: 0

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

Insufficient policy enforcement in PopupBlocker in Google Chrome prior to 91.0.4472.77 allowed a remote attacker to bypass navigation restrictions via a crafted iframe.

CVSS v3
6.5
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
17%
EPSS %ILE
97%
KEV
⚠ Exploited

Published

June 7, 2021

Last Modified

October 24, 2025

Advisory Details (5)

Auto-updated Jun 12, 2026
No patch confirmed yet.
generic

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

https://security.gentoo.org/glsa/202107-06
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
https://crbug.com/1145553
generic

Chrome Releases: Stable Channel Update for Desktop

https://chromereleases.googleblog.com/2021/05/stable-channel-update-for-desktop_25.html

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
chromium90.0.4430.212-193.0.4577.82-1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
chromium—93.0.4577.82-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
chromium—93.0.4577.82-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
chromium—93.0.4577.82-1—

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 103× in last 7d / 423× 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 1,526 total refreshes for this CVE.

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

Related CVEs(same CWE)

Frequently asked(6)

What is CVE-2021-30533?
CVE-2021-30533 is a critical vulnerability published on June 7, 2021. Insufficient policy enforcement in PopupBlocker in Google Chrome prior to 91.0.4472.77 allowed a remote attacker to bypass navigation restrictions via a crafted iframe.
When was CVE-2021-30533 disclosed?
CVE-2021-30533 was first published in the National Vulnerability Database on June 7, 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-2021-30533 actively exploited?
Yes. CISA added CVE-2021-30533 to the Known Exploited Vulnerabilities catalog on June 27, 2022, affecting Google Chromium PopupBlocker. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2021-30533?
CVE-2021-30533 has a CVSS v3 base score of 6.5 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0.
Which products are affected by CVE-2021-30533?
CVE-2021-30533 affects Google Chromium PopupBlocker. 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-2021-30533?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-30533, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2021-30533

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