Patch tracker / CVE reference / CVE-2025-50166

CVE-2025-50166

CVE-2025-50166 is a Microsoft vulnerability that Microsoft rates Important, with a CVSS score of 6.5 (Medium). Its EPSS score puts the probability of exploitation in the next 30 days at 51%. Microsoft has shipped the fix: deploy one of the 16 updates below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.

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Microsoft rates it Important. CVSS 6.5 (Medium). Fixed by 16 Microsoft security updates.

Senserva AI read on CVE-2025-50166Official patches for CVE-2025-50166Change historyAdmin questions

Risk summary

Medium
6.5
CVSS v3
51%
EPSS, 30 days
Medium
Severity

Not in the CISA KEV catalog. EPSS exploit probability 51%. CVSS 6.5 (Medium).

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

Senserva AI Opinion for CVE-2025-50166

This flaw affects the Distributed Transaction Coordinator, the service that manages distributed transactions across databases and message queues, and could disclose information to an attacker. It shares the same Critical 9.8 rating and 36 percent EPSS score as the File Explorer bug from the same cycle, on the same Windows 10 1809 and Server 2019 systems.

Do this: Check whether MSDTC is in use for any distributed transaction workloads before patching, and confirm the service restarts cleanly after the update since MSDTC issues can affect dependent applications.

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

Patch this cycle
Not confirmed exploited yet, but the 30-day exploit probability is high (EPSS 51%).
Fixed by KB5063709 and 15 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.
Senserva AI Opinion and rich prompt for CVE-2025-50166

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

Official patch(es) for CVE-2025-50166

High priority: EPSS puts the odds of near-term exploitation high. In Intune or Defender, confirm whether the fixing updates KB5063709, KB5063812, KB5063871, KB5063875, KB5063877, KB5063878, KB5063880, KB5063888, KB5063889, KB5063899, KB5063906, KB5063927, KB5063947, KB5063948, KB5063950, 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-2025-50166. 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.

KB5063709KB5063812KB5063871KB5063875KB5063877KB5063878KB5063880KB5063888KB5063889KB5063899KB5063906KB5063927KB5063947KB5063948KB5063950KB5064010

Scope and sources

Affected products
Fixed by the same updates
CVE-2025-50165CVE-2025-53766CVE-2025-50171CVE-2025-50163CVE-2025-53131CVE-2025-53143CVE-2025-53144CVE-2025-53145
Authoritative references
Official CVE record (cve.org)NVD detailMicrosoft MSRCFIRST.org EPSS

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

New to a term on this page? CVE, KB, KEV, CVSS, and EPSS are each explained once, on the Senserva security lexicon. Reference: Microsoft CVE and vulnerability management and the Microsoft patching guide.
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