CVE-2026-21243

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-02-10. NVD baseline CVSS 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 7.5Exploit: NoneExposed: 0

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

Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to deny service over a network.

CVSS v3
7.5
EG Score
7.5(medium)
EPSS
68.1%
KEV
Not listed

Published

February 10, 2026

Last Modified

February 11, 2026

Advisory Details (1)

Auto-updated Jun 10, 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-2026-21243

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-21243?
CVE-2026-21243 is a high vulnerability published on February 10, 2026. Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an unauthorized attacker to deny service over a network.
When was CVE-2026-21243 disclosed?
CVE-2026-21243 was first published in the National Vulnerability Database on February 10, 2026, with the most recent update on February 11, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-21243 actively exploited?
CVE-2026-21243 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 68.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-21243?
CVE-2026-21243 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-21243?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-21243, 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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