Cyber Resilience

CVE-2025-53739

High

Published: 12 August 2025

Published
12 August 2025
Modified
15 August 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 0.0104 77.8th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-53739 is a high-severity Type Confusion (CWE-843) vulnerability in Microsoft Office Long Term Servicing Channel. Its CVSS base score is 7.8 (High).

Operationally, ranked in the top 22.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis

CVE-2025-53739 is a type confusion vulnerability, tracked as CWE-843, that affects Microsoft Office Excel. The flaw permits an unauthorized attacker to execute arbitrary code on an affected system when a specially crafted file is processed.

An attacker can exploit the issue locally without any privileges by convincing a user to open a malicious Excel document, resulting in full compromise of confidentiality, integrity, and availability on the target host under the CVSS vector AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Microsoft has published an advisory for CVE-2025-53739 that includes remediation guidance. The associated EPSS score remains low and unchanged at 0.0104 with no observed upward trajectory after disclosure.

EU & UK References

Vulnerability details

Access of resource using incompatible type ('type confusion') in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

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

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References