Cyber Resilience

CVE-2025-27747

Microsoft Office Long Term Servicing Channel 2021 … 2024

Published
08 April 2025
Modified
09 July 2025
Patch / advisory
View advisory
CVSS Score v3.1 7.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.0079 53th percentile
Risk Priority 59 floored blend · peak EPSS

Summary

CVE-2025-27747 is a high-severity Untrusted Pointer Dereference (CWE-822) 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 Privilege Escalation (T1068); ranked in the top 47% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

The vulnerability is a use-after-free flaw, tracked as CWE-822, that affects Microsoft Office Word and carries a CVSS 3.1 score of 7.8. It permits an unauthorized attacker to execute arbitrary code on an affected system when certain conditions are met.

An attacker can trigger the issue locally by supplying a malicious document that the victim must open, requiring no privileges but relying on user interaction. Successful exploitation grants the attacker full control over confidentiality, integrity, and availability on the target host.

Microsoft has published an advisory describing the issue and available updates at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-27747. The EPSS probability has climbed from a low baseline of 0.0060 to a recorded peak of 0.0121, indicating that exploitation interest emerged after disclosure.

EU & UK References

Vulnerability Data

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

CWE(s)
CWE-822

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-54905Same product: Microsoft 365 Apps
CVE-2026-40367Same product: Microsoft 365 Apps
CVE-2026-20948Same product: Microsoft 365 Apps
CVE-2026-26113Same product: Microsoft 365 Apps
CVE-2025-24083Same product: Microsoft 365 Apps
CVE-2023-36045Same product: Microsoft 365 Apps
CVE-2026-20955Same product: Microsoft 365 Apps
CVE-2025-21354Same product: Microsoft 365 Apps
CVE-2026-26112Same product: Microsoft 365 Apps
CVE-2025-21381Same product: Microsoft 365 Apps

Affected Assets

microsoft
365 apps
all versions
microsoft
office
2019
microsoft
office long term servicing channel
2021, 2024
microsoft
sharepoint enterprise server
2016
microsoft
sharepoint server
2019
microsoft
word
2016

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation can discover instances where untrusted data is turned into a pointer and dereferenced.

SI-10 Information Input Validation good match

Validating all information inputs stops untrusted values from being accepted and converted into dereferenceable pointers.

SI-16 Memory Protection partial match

Memory-protection mechanisms limit the damage from an invalid pointer dereference without stopping the root coding flaw.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly prevent introduction of untrusted pointer handling during development.

DE.CM-09 partial match
prevents

Runtime monitoring of software and data can detect adverse events resulting from exploitation of the weakness.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover instances of this weakness via code review or scanning.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect pointer-dereference flaws before release.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle includes pointer-safety practices that reduce untrusted pointer dereference risk.

A.8.26 Application security requirements partial match
prevents

Application security requirements can mandate validation of pointers obtained from untrusted sources.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles discourage direct use of untrusted values as pointers.

A.8.28 Secure coding partial match
prevents

Secure coding standards explicitly forbid dereferencing pointers derived from untrusted input.

References