SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-66806

Off-by-one error in Microsoft Office Word allows an unauthorized attacker to disclose information locally.

MEDIUM 5.5EPSS 0.31%

Does this matter?

Lower severity and a low EPSS score (0.31%). Track it; it rarely justifies an emergency change on its own.

Description

Off-by-one error in Microsoft Office Word allows an unauthorized attacker to disclose information locally.

CVSS 3.1
5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS
0.31% probability · 23th percentile
CISA KEV
Not listed
Weakness
CWE-125, CWE-193
Affected
microsoft/365 apps · microsoft/office 2019 · microsoft/office 2021 · microsoft/office 2024 · microsoft/word
Source
secure@microsoft.com

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