SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2025-21266

Windows Telephony Service Remote Code Execution Vulnerability

HIGH 8.8EPSS 1.27%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.27%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Windows Telephony Service Remote Code Execution Vulnerability

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
1.27% probability · 68th percentile
CISA KEV
Not listed
Weakness
CWE-122
Affected
microsoft/windows 10 1507 · microsoft/windows 10 1607 · microsoft/windows 10 1809 · microsoft/windows 10 21h2 · microsoft/windows 10 22h2 · microsoft/windows 11 22h2 · microsoft/windows 11 23h2 · microsoft/windows 11 24h2 · microsoft/windows server 2008 · microsoft/windows server 2012 · microsoft/windows server 2016 · microsoft/windows server 2019 · microsoft/windows server 2022 · microsoft/windows server 2022 23h2 · microsoft/windows server 2025
Source
secure@microsoft.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.