Cyber Posture

CVE-2025-49697

High

Published: 08 July 2025

Published
08 July 2025
Modified
15 July 2025
KEV Added
Patch
CVSS Score 8.4 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0062 70.0th percentile
Risk Priority 17 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-49697 is a high-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Microsoft Office Long Term Servicing Channel. Its CVSS base score is 8.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked in the top 30.0% 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 RA-5 (Vulnerability Monitoring and Scanning) and SI-16 (Memory Protection).

Threat & Defense at a Glance

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

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly requires timely flaw remediation through patching the heap-based buffer overflow vulnerability in Microsoft Office as specified in CVE-2025-49697.

prevent

Implements memory protection mechanisms such as ASLR and DEP that directly mitigate heap-based buffer overflow exploits enabling arbitrary code execution.

detect

Provides vulnerability scanning to identify Microsoft Office installations affected by CVE-2025-49697 for subsequent remediation.

MITRE ATT&CK Enterprise TechniquesAI

T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
Why these techniques?

Heap buffer overflow in Microsoft Office directly enables local arbitrary code execution via client application exploitation (T1203).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.

Deeper analysisAI

CVE-2025-49697, published on 2025-07-08, is a heap-based buffer overflow vulnerability (CWE-122) affecting Microsoft Office. The issue carries a CVSS v3.1 base score of 8.4 (AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating high severity due to its potential for significant impact on confidentiality, integrity, and availability.

The vulnerability can be exploited by an unauthorized local attacker requiring only low-complexity techniques, no privileges, and no user interaction. Successful exploitation allows the attacker to execute arbitrary code on the affected system.

Microsoft's Security Response Center provides mitigation and patching guidance in the update guide at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-49697.

Details

CWE(s)

Affected Products

microsoft
365 apps
all versions
microsoft
office
2016, 2019, all versions
microsoft
office long term servicing channel
2021, 2024
microsoft
office online server
≤ 16.0.10417.20027

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References