CVE-2023-21674

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 2023-01-10), 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: 42%CVSS: 8.8Exploit: cisa kev · ssvc active · epss top5pct · public exploitExposed: 0

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

Windows Advanced Local Procedure Call (ALPC) Elevation of Privilege Vulnerability

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
42%
EPSS %ILE
99%
KEV
⚠ Exploited

Published

January 10, 2023

Last Modified

October 30, 2025

Advisory Details (2)

Auto-updated Jun 2, 2026
⚠️ Active exploitation confirmed. Patch available. Sources: microsoft, cisa.
cisa Patch Available🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-21674
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-2023-21674

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 89× in last 7d / 381× 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 1,269 total refreshes for this CVE.

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

Frequently asked(6)

What is CVE-2023-21674?
CVE-2023-21674 is a critical vulnerability published on January 10, 2023. Windows Advanced Local Procedure Call (ALPC) Elevation of Privilege Vulnerability
When was CVE-2023-21674 disclosed?
CVE-2023-21674 was first published in the National Vulnerability Database on January 10, 2023, with the most recent update on October 30, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2023-21674 actively exploited?
Yes. CISA added CVE-2023-21674 to the Known Exploited Vulnerabilities catalog on January 10, 2023, affecting Microsoft Windows. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2023-21674?
CVE-2023-21674 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-2023-21674?
CVE-2023-21674 affects Microsoft Windows. 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-2023-21674?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2023-21674, 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-2023-21674

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