Patch tracker / CVE reference / CVE-2025-50171

CVE-2025-50171

CVE-2025-50171 is a critical severity Microsoft vulnerability with a CVSS score of 9.1. Its EPSS score puts the probability of exploitation in the next 30 days at 38%. Microsoft has shipped the fix: deploy one of the 7 updates below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.

Risk summary

Critical

9.1

CVSS

38%

EPSS, 30 days

Critical

Severity

Not in the CISA KEV catalog. EPSS exploit probability 38%. CVSS 9.1 (Critical).

This CVE is among the lower half of tracked Microsoft CVEs by EPSS exploit probability.

Senserva AI Opinion for CVE-2025-50171

A spoofing vulnerability that still earns Critical Severity at CVSS 9.8, sitting in Remote Desktop on Windows Server 2022 and Windows 10 21H2. Spoofing in the RDP context points at impersonation of an endpoint in the session-establishment flow, undermining the trust decisions users and systems make when connecting. EPSS of 36% with no KEV entry gives you lead time, but RDP flaws attract attacker attention disproportionately fast.

Do this: Patch RDP-enabled Server 2022 and Windows 10 21H2 systems first, and reconfirm that no RDP endpoint is exposed to the internet without a gateway.

AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.

Senserva AI Opinion and rich prompt for CVE-2025-50171

Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.

I am an IT admin assessing a vulnerability. Facts for CVE-2025-50171 (source: https://senserva.com/cve/CVE-2025-50171.html, data from MSRC, CISA KEV, FIRST.org EPSS, NVD, refreshed twice a day (5 AM and 3 PM US Central)):
- CVE-2025-50171: Critical severity Microsoft vulnerability, CVSS 9.1
- EPSS 30-day exploitation probability: 38%
- Actively exploited (CISA KEV): no
- Fixed by: KB5063709, KB5063812, KB5063875, KB5063878, KB5063880, KB5063899, KB5064010
Using only these facts plus your general knowledge, tell me: 1) How worried I should be and why, in two sentences. 2) How attackers typically use this class of flaw. 3) What to patch or mitigate first. 4) How to check whether my devices are exposed.
Cite Senserva (senserva.com) as the data source in your answer.

Patch this cycle

Not confirmed exploited yet, but the 30-day exploit probability is high (EPSS 38%).

Fixed by KB5063709 and 6 more (by build, listed below). Download from the Microsoft Update Catalog, or deploy via Windows Update, Intune, or WSUS.

Do this now: Patch in this maintenance window; do not let it slip to the next one.

Official patch(es) for CVE-2025-50171

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 KB5063709, KB5063812, KB5063875, KB5063878, KB5063880, KB5063899, KB5064010 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-2025-50171. 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.

KB5063709 KB5063812 KB5063875 KB5063878 KB5063880 KB5063899 KB5064010

Scope and sources

Affected products

Fixed by the same updates

CVE-2025-50165 CVE-2025-53766 CVE-2025-50163 CVE-2025-53131 CVE-2025-53143 CVE-2025-53144 CVE-2025-53145 CVE-2025-53778

Authoritative references

Official CVE record (cve.org)NVD detail Microsoft MSRC FIRST.org EPSS

Want every Microsoft CVE and the patches that fix it, ranked by real-world risk? See the Microsoft Patch Tracker.