CVE-2026-66323

MEDIUMPre-NVD 5.45.4—
EchelonGraph scoreHIGH confidence

Score 5.4 from GitHub Security Advisory published 2026-08-28. a secondary CVSS source baseline 5.4; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 5 sources updated this week
5.4EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.4Exploit: None knownExposed: 0

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

Improper neutralization of parameter/argument delimiters in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.

CVSS v3
5.4
EG Score
5.4(high)
EG Risk
24(Track)
EG Risk 24/100SSVC: 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
Severity54% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
22%
KEV
Not listed

Published

August 28, 2026

Last Modified

August 30, 2026

Advisory Details (1)

Auto-updated Aug 28, 2026
Patch available. Sources: microsoft.
microsoft Patch Available

Security Update Guide - Microsoft Security Response Center

Security Update Guide - Microsoft Security Response Center. Patch available via Microsoft Security Update

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66323

Vendor Advisories for CVE-2026-66323(1)

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

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 20× in last 7d / 20× 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. 2026-08-30 01:30 UTCEG score recompute
  2. 2026-08-30 01:30 UTCVendor advisory
  3. 2026-08-30 01:30 UTCGHSA enrichment
  4. 2026-08-30 01:22 UTCEPSS rescore
  5. 2026-08-30 01:09 UTCVendor advisory
  6. 2026-08-30 01:09 UTCGHSA enrichment
  7. 2026-08-29 16:36 UTCEG score recompute
  8. 2026-08-29 16:36 UTCVendor advisory
  9. 2026-08-29 16:36 UTCGHSA enrichment
  10. 2026-08-29 04:27 UTCEG score recompute
  11. 2026-08-29 04:27 UTCVendor advisory
  12. 2026-08-29 04:26 UTCGHSA enrichment
  13. 2026-08-29 04:05 UTCEG score recompute
  14. 2026-08-29 04:05 UTCVendor advisory
  15. 2026-08-29 04:05 UTCGHSA enrichment
  16. 2026-08-28 20:25 UTCEG score recompute
  17. 2026-08-28 20:25 UTCVendor advisory
  18. 2026-08-28 19:39 UTCEG score recompute
  19. 2026-08-28 19:39 UTCVendor advisory
  20. 2026-08-28 19:36 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-66323?
CVE-2026-66323 is a medium vulnerability published on August 28, 2026. Improper neutralization of parameter/argument delimiters in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.
When was CVE-2026-66323 disclosed?
CVE-2026-66323 was first published in the National Vulnerability Database on August 28, 2026, with the most recent update on August 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-66323 actively exploited?
CVE-2026-66323 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 78.0% of all scored CVEs.
What is the CVSS score of CVE-2026-66323?
CVE-2026-66323 has a CVSS v3 base score of 5.4 (NVD).
How do I remediate CVE-2026-66323?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-66323, 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-2026-66323

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