CVE-2026-65656

Status: AnalyzedHigh (7.8)—

Improper neutralization of special elements used in a command ('command injection') in Microsoft Office allows an unauthorized attacker to execute code locally.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Base score: 7.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.46%
Percentile among all scored CVEs: 38
Score date: 10/4/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1203 Exploitation for Client Executionexecution85 %
Primary impactT1059 Command and Scripting Interpreterexecution90 %

Vector AV:L + UI:R indica ejecución en cliente tras interacción del usuario (abrir archivo). CWE-77 (command injection) en Office causa ejecución de código arbitrario.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Restrict Web-Based Content Privileged Account Management Limit Software Installation Execution Prevention Behavior Prevention on Endpoint Disable or Remove Feature or Program

Affected technologies (4)

Microsoft — 365 Apps Microsoft — Office 2019 Microsoft — Office 2021 Microsoft — Office 2024

CWEs

CWE-77

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-65656

Raw JSON (NVD)

Show

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