SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-31179

Microsoft Office Remote Code Execution Vulnerability

HIGH 7.8EPSS 13.5%

Does this matter?

EPSS puts the probability of exploitation in the next 30 days at 13.5%, higher than 96% of all known CVEs. Patch or mitigate before the next change window.

Description

Microsoft Office Remote Code Execution Vulnerability

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
13.49% probability · 96th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Affected
microsoft/365 apps · microsoft/excel · microsoft/office · microsoft/office online server · microsoft/office web apps server
Source
secure@microsoft.com
EPSS trend
0%8%15%3 November 2026: 13.49%3 November 20263 November 2026

EPSS 13.5% since 3 November 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

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