VulnerabilityModified

CVE-2021-26877

Windows DNS Server Remote Code Execution Vulnerability

CRITICAL 9.8EPSS 17.3%

Does this matter?

EPSS puts the probability of exploitation in the next 30 days at 17.3%, higher than 97% of all known CVEs. Patch or mitigate before the next change window.

Description

Windows DNS Server Remote Code Execution Vulnerability

CVSS 3.1: 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 17.29% probability · 97th percentile
Public exploits: None in Exploit-DB
CISA KEV: Not listed
Affected: microsoft/windows server 2008 · microsoft/windows server 2012 · microsoft/windows server 2016 · microsoft/windows server 2019
Source: secure@microsoft.com

EPSS trend

EPSS moved from 17.6% on 30 September 2026 to 17.3% on 26 October 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.