CVE-2026-45458

Status: ModifiedHigh (8.4)—

Use after free 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:N/S:U/C:H/I:H/A:H
Base score: 8.4

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.45%
Percentile among all scored CVEs: 37
Score date: 10/5/2026

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.

ExploitationT1068 Exploitation for Privilege Escalationprivilege escalation95 %
Primary impactT1059 Command and Scripting Interpreterexecution90 %

CWE-416 (use-after-free) con acceso local sin privilegios ni interacción del usuario (AV:L, PR:N, UI:N) permite escalada a ejecución de código arbitrario; vector CVSS confirma impacto crítico (C:H, I:H, A:H).

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

Execution Prevention Threat Intelligence Program Restrict Web-Based Content Privileged Account Management Limit Software Installation Behavior Prevention on Endpoint

Affected technologies (7)

Microsoft — 365 Apps Microsoft — Microsoft 365 Microsoft — Office 2019 Microsoft — Office 2021 Microsoft — Office 2024 Microsoft — Sharepoint Server Microsoft — Word

CWEs

CWE-416

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45458

Raw JSON (NVD)

Show

{
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      "value": "Use after free in Microsoft Office allows an unauthorized attacker to execute code locally."
    },
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  ],
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}