Cyber Resilience

CVE-2025-26630

High

Published: 11 March 2025

Published
11 March 2025
Modified
03 July 2025
KEV Added
Patch
CVSS Score v3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0055 68.5th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-26630 is a high-severity Use After Free (CWE-416) vulnerability in Microsoft Office Long Term Servicing Channel. Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked in the top 31.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SI-16 (Memory Protection) and SI-2 (Flaw Remediation).

Deeper analysis

CVE-2025-26630 is a use-after-free vulnerability (CWE-416) affecting Microsoft Office Access. Published on 2025-03-11, it carries a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H). The flaw enables an unauthorized attacker to execute code locally on a system running the affected component.

Exploitation requires local access to the target system, low attack complexity, and no privileges from the attacker, though user interaction is necessary, such as opening a malicious file. A successful attack allows arbitrary code execution, resulting in high impacts to confidentiality, integrity, and availability.

Microsoft's Security Response Center provides guidance on updates and mitigation in its advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-26630.

EU & UK References

Vulnerability details

Use after free in Microsoft Office Access allows an unauthorized attacker to execute code locally.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1204.002 Malicious File Execution
An adversary may rely upon a user opening a malicious file in order to gain execution.
Why these techniques?

The use-after-free vulnerability in Microsoft Office Access enables arbitrary code execution upon opening a malicious file, directly mapping to T1203 (Exploitation for Client Execution) and T1204.002 (Malicious File under User Execution).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

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CVE-2025-24079Same product: Microsoft 365 Apps
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CVE-2025-24082Same product: Microsoft 365 Apps
CVE-2026-20950Same product: Microsoft 365 Apps
CVE-2025-21186Same product: Microsoft 365 Apps
CVE-2025-24080Same product: Microsoft 365 Apps
CVE-2025-21386Same product: Microsoft 365 Apps

Affected Assets

microsoft
365 apps
all versions
microsoft
access
2016
microsoft
office
2019
microsoft
office long term servicing channel
2021, 2024

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Flaw remediation requires timely patching of the use-after-free vulnerability in Microsoft Office Access as provided in the vendor advisory.

prevent

Memory protection mechanisms such as ASLR, DEP, and control flow guard directly mitigate exploitation of use-after-free vulnerabilities by preventing unauthorized code execution.

preventdetect

Malicious code protection scans Office files for threats and can block or detect malicious Access documents requiring user interaction to exploit.

References