CVE-2026-21514highunder attackCWE-807

CVE-2026-21514: high-severity vulnerability in Microsoft 365 Apps for Enterprise

Microsoft Word Security Feature Bypass Vulnerability

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51Vexday Risk Score

Prioritize patching. It under exploitation confirmed by CISA and has an official Brazilian government alert.

ssvc Actcvss 7.8epss 1.6%
from disclosure to weapon
Published on NVDFeb 10
CISA KEVFeb 10
Official alert in Brazil

Brazil's federal government published an alert, recommendation or bulletin that cites this vulnerability.

Source: CTIR Gov (GSI) and CISC Gov.br, under the CC BY-ND 3.0 license.
Action required by CISAfederal deadline: 2026-03-03

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

In short

Microsoft Word relies on untrusted data to make security decisions, allowing attackers to bypass security protections on a local computer. This means malicious files or inputs can trick Word into ignoring its safety measures.

Technical detail

CWE-807 vulnerability in Word's security decision logic accepts untrusted input without proper validation, enabling local attackers to circumvent security features. Requires local access and interaction with a malicious file; impact includes bypassing protected view and macro execution controls.

Summary generated and translated by AI from the official description.

The full analysis of this CVE is available in Portuguese →

Reliance on untrusted inputs in a security decision in Microsoft Office Word allows an unauthorized attacker to bypass a security feature locally.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
Affected products
Microsoft · Microsoft 365 Apps for EnterpriseMicrosoft · Microsoft Office LTSC 2021Microsoft · Microsoft Office LTSC 2024Microsoft · Microsoft Office LTSC for Mac 2021Microsoft · Microsoft Office LTSC for Mac 2024
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