Patch tracker / CVE reference / CVE-2026-20945
CVE-2026-20945
CVE-2026-20945 is a medium severity Microsoft vulnerability with a CVSS score of 6.5. Its EPSS score puts the probability of exploitation in the next 30 days at 25%. Microsoft has shipped the fix: deploy one of the 5 updates below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.
Medium severity Microsoft vulnerability, CVSS 6.5. Fixed by 5 Microsoft security updates.
Risk summary
Updated July 23, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.
Senserva AI Opinion for CVE-2026-20945
This is a spoofing flaw in on-premises SharePoint (2016 Enterprise, 2019, and Subscription Edition), so it hits organizations still running their own SharePoint farms rather than SharePoint Online. Although rated Medium severity (CVSS 6.5) and not in CISA KEV, the 25 percent EPSS score is notably high for a spoofing bug, suggesting attackers may find it worth weaponizing to impersonate trusted content or users. Spoofing on a collaboration platform is commonly a stepping stone for phishing or social engineering inside your own tenant.
Do this: Identify all on-premises SharePoint 2016, 2019, and Subscription Edition farms and schedule Microsoft's patch for CVE-2026-20945 in your next maintenance window.
AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2026-20945
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for CVE-2026-20945
Published and last-revised dates are authoritative, from Microsoft MSRC (or the CISA KEV date-added). Senserva additionally records day-to-day changes from 2026-07-07, refreshed several times a day; the change count reflects that forward-only tracking.
Exploitation and severity
Not in the CISA KEV catalog. EPSS exploit probability 25%. CVSS 6.5 (Medium).
This CVE is among the top half of tracked Microsoft CVEs by EPSS exploit probability.
Official patch(es) for CVE-2026-20945
Elevated priority: high severity or a meaningful exploitation probability, sooner if an affected product is internet-facing. In Intune or Defender, confirm whether the fixing updates KB5002853, KB5002854, KB5002856, KB5002861, KB5002862 are installed across the affected products. Senserva does this automatically across your tenant and flags every missing patch.
Apply the Microsoft security updates below to fix CVE-2026-20945. Each KB page carries the Microsoft Update Catalog download, Microsoft's known issues for the update, a copy-paste PowerShell check for whether it is installed, and the Senserva AI read.
Affected products
Common questions about CVE-2026-20945
Is CVE-2026-20945 actively exploited?
It is not currently listed in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score puts the probability of exploitation in the next 30 days at 25%.
What patch fixes CVE-2026-20945?
Microsoft fixed CVE-2026-20945 in KB5002853, KB5002854, KB5002856, KB5002861, KB5002862. Download from the Microsoft Update Catalog, or let Intune, Windows Update, or WSUS deliver it.
Which products are affected by CVE-2026-20945?
Microsoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019, Microsoft SharePoint Server Subscription Edition.
Can I ask my own AI about CVE-2026-20945?
Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2026-20945's key facts: severity, CVSS, EPSS exploit probability, CISA KEV status, and the fixing KB. Copy it into Claude, ChatGPT, or Copilot for a triage plan; the data is refreshed three times a day (5 AM, 12:30 PM, and 7 PM US Central).
Fixed by the same updates
If you are patching CVE-2026-20945, the same updates also fix these:
Authoritative references
Want every Microsoft CVE and the patches that fix it, ranked by real-world risk? See the Microsoft Patch Tracker.
