Patch tracker / CVE reference / CVE-2025-21393
CVE-2025-21393
CVE-2025-21393 is a high severity Microsoft vulnerability with a CVSS score of 7.8. 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.
High severity Microsoft vulnerability, CVSS 7.8. Fixed by 5 Microsoft security updates.
Risk summary
Updated July 28, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.
Senserva AI Opinion for CVE-2025-21393
SharePoint Server, across the same Enterprise 2016 through Subscription Edition range as the other SharePoint findings in this batch, has a spoofing vulnerability here rated High 7.8 with a low 2 percent EPSS score. Compared to the SharePoint denial of service bug elsewhere in this list, which carries a much higher 51 percent EPSS, this spoofing issue looks like a lower near-term priority within the SharePoint patch set. It is not confirmed exploited or tied to ransomware.
Do this: Patch SharePoint farms for this alongside the other SharePoint CVEs in this batch, but rank it behind the higher-EPSS SharePoint denial of service fix.
AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2025-21393
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for CVE-2025-21393
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 1.5%. CVSS 7.8 (High).
This CVE is among the lower half of tracked Microsoft CVEs by EPSS exploit probability.
Official patch(es) for CVE-2025-21393
Moderate priority: schedule it in your normal patch cycle. In Intune or Defender, confirm whether the fixing updates KB5002666, KB5002667, KB5002671, KB5002672, KB5002676 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-2025-21393. 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-2025-21393
Is CVE-2025-21393 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 1.5%.
What patch fixes CVE-2025-21393?
Microsoft fixed CVE-2025-21393 in KB5002666, KB5002667, KB5002671, KB5002672, KB5002676. Download from the Microsoft Update Catalog, or let Intune, Windows Update, or WSUS deliver it.
Which products are affected by CVE-2025-21393?
Microsoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019, Microsoft SharePoint Server Subscription Edition.
Can I ask my own AI about CVE-2025-21393?
Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2025-21393'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 twice a day (5 AM and 3 PM US Central).
Fixed by the same updates
If you are patching CVE-2025-21393, 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.
