CVE-2026-78966

MEDIUMPre-NVD 4.34.3—
EchelonGraph scoreHIGH confidence

Score 4.3 from GitHub Security Advisory published 2026-08-25. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 4.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 4 sources updated this week
4.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 4.3Exploit: None knownExposed: 0

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

Externally controlled reference in QUIC in Google Chrome prior to 152.0.7977.65 allowed a remote attacker to bypass web origin policy via a crafted HTML page. (Chromium security severity: Medium)

CVSS v3
4.3
Vendor severity
MEDIUMper Google (Chromium)Vendor's own band, not a CVSS rating — advisory text: (Chromium security severity: Medium)
EG Score
4.3(high)
EG Risk
20(Track)
EG Risk 20/100SSVC: 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
Severity43% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
39%
KEV
Not listed

Published

August 25, 2026

Last Modified

August 28, 2026

Advisory Details (2)

Auto-updated Aug 27, 2026
No patch confirmed yet.
generic

Chromium

https://issues.chromium.org/issues/497637694
generic

Chrome Releases: Stable Channel Update for Desktop

https://chromereleases.googleblog.com/2026/08/stable-channel-update-for-desktop_0256176589.html

Vendor Advisories for CVE-2026-78966(1)

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

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
chromium113.0.5672.126-1 ... 152.0.7977.64-1 (412 versions)152.0.7977.75-1~deb12u1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
chromium138.0.7204.183-1 ... 152.0.7977.75-1~deb12u1 (178 versions)152.0.7977.75-1~deb13u1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
chromium138.0.7204.183-1 ... 152.0.7977.75-1~deb13u1 (180 versions)——

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 28× in last 7d / 97× 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. 2026-09-19 07:28 UTCEG score recompute
  2. 2026-09-19 07:28 UTCVendor advisory
  3. 2026-09-19 07:28 UTCGHSA enrichment
  4. 2026-09-18 19:28 UTCEPSS rescore
  5. 2026-09-18 09:10 UTCEG score recompute
  6. 2026-09-18 09:10 UTCVendor advisory
  7. 2026-09-18 09:10 UTCGHSA enrichment
  8. 2026-09-17 10:52 UTCEG score recompute
  9. 2026-09-17 10:52 UTCVendor advisory
  10. 2026-09-17 10:52 UTCGHSA enrichment
  11. 2026-09-16 14:08 UTCEPSS rescore
  12. 2026-09-16 12:20 UTCEG score recompute
  13. 2026-09-16 12:20 UTCVendor advisory
  14. 2026-09-16 12:20 UTCGHSA enrichment
  15. 2026-09-16 05:15 UTCEPSS rescore
  16. 2026-09-15 14:02 UTCEG score recompute
  17. 2026-09-15 14:02 UTCVendor advisory
  18. 2026-09-15 14:02 UTCGHSA enrichment
  19. 2026-09-15 03:12 UTCEPSS rescore
  20. 2026-09-15 03:12 UTCEPSS rescore
  21. 2026-09-14 15:44 UTCVendor advisory
  22. 2026-09-14 15:44 UTCGHSA enrichment
  23. 2026-09-13 17:27 UTCEG score recompute
  24. 2026-09-13 17:27 UTCVendor advisory
  25. 2026-09-13 17:27 UTCGHSA enrichment
Show 72 more
  1. 2026-09-12 19:09 UTCEG score recompute
  2. 2026-09-12 19:09 UTCVendor advisory
  3. 2026-09-12 19:09 UTCGHSA enrichment
  4. 2026-09-11 20:51 UTCEG score recompute
  5. 2026-09-11 20:51 UTCVendor advisory
  6. 2026-09-11 20:51 UTCGHSA enrichment
  7. 2026-09-11 14:53 UTCEPSS rescore
  8. 2026-09-11 14:53 UTCEPSS rescore
  9. 2026-09-10 22:33 UTCEG score recompute
  10. 2026-09-10 22:33 UTCGHSA enrichment
  11. 2026-09-10 00:16 UTCGHSA enrichment
  12. 2026-09-09 01:09 UTCEG score recompute
  13. 2026-09-09 01:09 UTCVendor advisory
  14. 2026-09-09 01:09 UTCGHSA enrichment
  15. 2026-09-08 22:01 UTCEPSS rescore
  16. 2026-09-07 19:58 UTCEG score recompute
  17. 2026-09-07 19:58 UTCVendor advisory
  18. 2026-09-07 19:58 UTCGHSA enrichment
  19. 2026-09-06 21:40 UTCEG score recompute
  20. 2026-09-06 21:40 UTCVendor advisory
  21. 2026-09-06 21:40 UTCGHSA enrichment
  22. 2026-09-06 13:48 UTCEPSS rescore
  23. 2026-09-05 23:22 UTCEG score recompute
  24. 2026-09-05 23:22 UTCVendor advisory
  25. 2026-09-05 23:22 UTCGHSA enrichment
  26. 2026-09-05 01:03 UTCEG score recompute
  27. 2026-09-05 01:03 UTCVendor advisory
  28. 2026-09-05 01:03 UTCGHSA enrichment
  29. 2026-09-04 05:07 UTCEPSS rescore
  30. 2026-09-04 02:45 UTCVendor advisory
  31. 2026-09-04 02:45 UTCGHSA enrichment
  32. 2026-09-03 04:24 UTCEG score recompute
  33. 2026-09-03 04:24 UTCVendor advisory
  34. 2026-09-03 04:24 UTCGHSA enrichment
  35. 2026-09-02 14:12 UTCEPSS rescore
  36. 2026-09-02 06:05 UTCEG score recompute
  37. 2026-09-02 06:05 UTCVendor advisory
  38. 2026-09-02 06:05 UTCGHSA enrichment
  39. 2026-09-01 13:54 UTCEPSS rescore
  40. 2026-09-01 07:48 UTCEG score recompute
  41. 2026-09-01 07:48 UTCVendor advisory
  42. 2026-09-01 07:48 UTCGHSA enrichment
  43. 2026-09-01 04:40 UTCEPSS rescore
  44. 2026-09-01 04:40 UTCEPSS rescore
  45. 2026-08-31 09:25 UTCEG score recompute
  46. 2026-08-31 09:25 UTCVendor advisory
  47. 2026-08-31 09:25 UTCGHSA enrichment
  48. 2026-08-30 19:18 UTCEPSS rescore
  49. 2026-08-30 19:17 UTCEPSS rescore
  50. 2026-08-30 11:06 UTCEG score recompute
  51. 2026-08-30 11:06 UTCVendor advisory
  52. 2026-08-30 11:06 UTCGHSA enrichment
  53. 2026-08-30 01:22 UTCEPSS rescore
  54. 2026-08-29 12:48 UTCEG score recompute
  55. 2026-08-29 12:48 UTCVendor advisory
  56. 2026-08-29 12:48 UTCGHSA enrichment
  57. 2026-08-28 21:42 UTCEPSS rescore
  58. 2026-08-28 14:26 UTCGHSA enrichment
  59. 2026-08-28 00:33 UTCEG score recompute
  60. 2026-08-28 00:33 UTCGHSA enrichment
  61. 2026-08-27 23:25 UTCEG score recompute▼ 2.20
  62. 2026-08-27 23:25 UTCGHSA enrichment
  63. 2026-08-27 23:22 UTCMITRE cvelistV5CVSS v3 → 4.3 · severity → MEDIUM
  64. 2026-08-27 15:00 UTCGHSA enrichment
  65. 2026-08-27 14:25 UTCEPSS rescore
  66. 2026-08-26 16:42 UTCEG score recompute
  67. 2026-08-26 16:42 UTCGHSA enrichment
  68. 2026-08-26 14:47 UTCEPSS rescore
  69. 2026-08-25 21:33 UTCGHSA enrichment
  70. 2026-08-25 21:25 UTCNVD update
  71. 2026-08-25 20:31 UTCEG score recompute
  72. 2026-08-25 20:25 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-78966?
CVE-2026-78966 is a medium vulnerability published on August 25, 2026. Externally controlled reference in QUIC in Google Chrome prior to 152.0.7977.65 allowed a remote attacker to bypass web origin policy via a crafted HTML page. (Chromium security severity: Medium)
When was CVE-2026-78966 disclosed?
CVE-2026-78966 was first published in the National Vulnerability Database on August 25, 2026, with the most recent update on August 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-78966 actively exploited?
CVE-2026-78966 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 61.2% of all scored CVEs.
What is the CVSS score of CVE-2026-78966?
CVE-2026-78966 has a CVSS v3.1 base score of 4.3 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-78966?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-78966, 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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