365 Apps
CVE-2025-21354
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2021 - Vulnerable and Outdated Components
ASVS 5.0
V15 - Secure Coding and Architecture Untrusted pointer prevention
|
| Impact | CVSS score of 8.4 (HIGH). Attack characteristics: local attack vector, low complexity, no privileges required, no user interaction not required. EPSS exploitation probability: 1.54%. |
| Exploit ScenarioDerived | Successful exploitation could compromise the high-severity affected system. |
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Alert meAnalysisAIv1 – Mar 28, 2026
Microsoft Excel Remote Code Execution Vulnerability. Rated high severity (CVSS 8.4), this vulnerability is no authentication required, low attack complexity.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affects your stack
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Technical ContextAI · show details
This vulnerability is classified under CWE-822. Affected products include: Microsoft 365 Apps, Microsoft Office, Microsoft Office Long Term Servicing Channel, Microsoft Office Online Server.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
Lifecycle Timeline
2DescriptionCVE.org
Microsoft Excel Remote Code Execution Vulnerability
Executive ViewAI
CVE-2025-21354 presents notable security risk rated CVSS 8.4. Successful exploitation could significantly impact the confidentiality, integrity, or availability of affected systems. A patch is available and should be applied as part of regular vulnerability management.
Apply vendor patch. If immediate patching is not feasible: (1) Implement network-level access controls to limit exposure; (2) Enable enhanced monitoring and alerting; (3) Apply principle of least privilege.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
Affected Products (CPE)CVE.org
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Microsoft Excel Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentica
Use-after-free vulnerability in Microsoft Office Word that allows local, unauthenticated attackers to execute arbitrary
Microsoft Excel Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely expl
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GitHub PoC
Exploit-DB