CVE-2026-50522

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreHIGH confidence

Score elevated to 9.8 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2026-07-22), indicating real-world exploitation has been confirmed by US federal agencies. the CNA's CVSS baseline 9.8 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
9.8EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS PROB: 85%CVSS: 9.8Exploit: cisa kev · ssvc active · epss top5pct · epss high · public exploitExposed: 0

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

Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.

CVSS v3
9.8
EG Score
9.8(high)
EG Risk
99(Act)
EG Risk 99/100SSVC: Act

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
Severity98% × 45%
Exploitation100% × 40%
Automatability100% × 15%
Action: Fix now — active exploitation, automatable, high impact.
EPSS PROB
85%
EPSS %ILE
100%
KEV
⚠ Exploited

Published

July 14, 2026

Last Modified

September 17, 2026

Advisory Details (1)

Auto-updated Sep 17, 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-2026-50522

Vendor Advisories for CVE-2026-50522(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 89× in last 7d / 374× 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 812 total refreshes for this CVE.

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

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 PoCWismanSec/sharepoint-2026-poc
    First seen Jul 26, 2026

    PoC, IOCs, and detection logic for the SharePoint /_trust WS-Federation BinaryFormatter deserialization chain. Lab reconstruction covering unauthenticated RCE, in-process machine key theft, and the artifacts each variant leaves behind. SharePoint 2016, 2019, and Subscription Edition. CVE-2026-50522, CVE-2026-45659, CVE-2026-56164, CVE-2026-58644.

    Open source ↗
  • GitHub PoC4minx/CVE-2026-50522
    First seen Jul 25, 2026

    CVE-2026-50522 PoC

    Open source ↗

Related CVEs(same CWE)

Frequently asked(6)

What is CVE-2026-50522?
CVE-2026-50522 is a critical vulnerability published on July 14, 2026. Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
When was CVE-2026-50522 disclosed?
CVE-2026-50522 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-2026-50522 actively exploited?
Yes. CISA added CVE-2026-50522 to the Known Exploited Vulnerabilities catalog on July 22, 2026, affecting Microsoft SharePoint. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2026-50522?
CVE-2026-50522 has a CVSS v4.0 base score of 9.8 (CNA self-assessment; NVD's own analysis pending).
Which products are affected by CVE-2026-50522?
CVE-2026-50522 affects Microsoft SharePoint. 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-2026-50522?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-50522, 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-2026-50522

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