Cyber Posture

CVE-2025-26630

High

Published: 11 March 2025

Published
11 March 2025
Modified
03 July 2025
KEV Added
Patch
CVSS Score 7.8 CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0049 65.8th 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 34.2% 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).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploitation for Client Execution (T1203) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

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.

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

NVD Description

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

Deeper analysisAI

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.

Details

CWE(s)

Affected Products

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

CVEs Like This One

CVE-2025-21366Same product: Microsoft 365 Apps
CVE-2025-21345Same product: Microsoft 365 Apps
CVE-2025-21392Same product: Microsoft 365 Apps
CVE-2025-24079Same product: Microsoft 365 Apps
CVE-2026-20952Same product: Microsoft 365 Apps
CVE-2025-62557Same product: Microsoft 365 Apps
CVE-2025-21395Same product: Microsoft 365 Apps
CVE-2025-21386Same product: Microsoft 365 Apps
CVE-2025-49695Same product: Microsoft 365 Apps
CVE-2026-20950Same product: Microsoft 365 Apps

References