CVE-2026-56164

CRITICALPre-NVD 5.39.0▲
EchelonGraph scoreHIGH confidence

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2026-07-14), indicating real-world exploitation has been confirmed by US federal agencies. the CNA's CVSS baseline 5.3 retained for reference (NVD's own analysis pending). Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, cna:microsoft, epss, ghsa
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: 27%CVSS: 5.3Exploit: 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.

Missing authentication for critical function in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.

CVSS v3
5.3
EG Score
9.0(high)
EG Risk
96(Attend)
EG Risk 96/100SSVC: 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%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
27%
EPSS %ILE
98%
KEV
⚠ Exploited

Published

July 14, 2026

Last Modified

September 17, 2026

Advisory Details (2)

Auto-updated Jul 14, 2026
⚠️ Active exploitation confirmed. Patch available. Sources: cisa, microsoft.
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-2026-56164
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-2026-56164

Vendor Advisories for CVE-2026-56164(2)

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.

Data Freshness Timeline

(refreshed 102× in last 7d / 427× 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 5,895 total refreshes for this CVE.

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

Publicly available exploits

(2 references)

Working exploit code is in the public domain (2 GitHub PoCs). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCsam00/POC-CVE-2026-56164-exploit
    First seen Aug 6, 2026

    CVE-2026-56164 is a critical missing-authentication vulnerability affecting on-premises Microsoft SharePoint Server. It allows unauthenticated, remote attackers to elevate privileges over a network.

    Open source ↗
  • GitHub PoCsentinel-aidefense/CVE-2026-56164-EXP
    First seen Jul 15, 2026

    CVE-2026-56164 EOP Exploit

    Open source ↗

Related CVEs(same CWE)

Frequently asked(6)

What is CVE-2026-56164?
CVE-2026-56164 is a critical vulnerability published on July 14, 2026. Missing authentication for critical function in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.
When was CVE-2026-56164 disclosed?
CVE-2026-56164 was first published in the National Vulnerability Database on July 14, 2026, with the most recent update on September 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-56164 actively exploited?
Yes. CISA added CVE-2026-56164 to the Known Exploited Vulnerabilities catalog on July 14, 2026, affecting Microsoft SharePoint Server. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2026-56164?
CVE-2026-56164 has a CVSS v4.0 base score of 5.3 (CNA self-assessment; NVD's own analysis pending). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0.
Which products are affected by CVE-2026-56164?
CVE-2026-56164 affects Microsoft SharePoint Server. 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-2026-56164?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-56164, 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-2026-56164

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