Cyber Posture

CVE-2025-49735

High

Published: 08 July 2025

Published
08 July 2025
Modified
13 February 2026
KEV Added
Patch
CVSS Score 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0096 76.6th percentile
Risk Priority 17 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-49735 is a high-severity Use After Free (CWE-416) vulnerability in Microsoft Windows Server 2012. Its CVSS base score is 8.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 23.4% 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 CM-7 (Least Functionality) and SI-16 (Memory Protection).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) 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

Directly remediates the use-after-free vulnerability in Windows KDC Proxy Service by requiring timely application of vendor patches as advised by Microsoft.

prevent

Implements memory protection mechanisms such as DEP, ASLR, and control flow guard to minimize successful exploitation of use-after-free vulnerabilities in KPSSVC.

prevent

Enforces least functionality by disabling the KDC Proxy Service when not required, eliminating the attack surface for remote code execution over the network.

MITRE ATT&CK Enterprise TechniquesAI

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.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
Why these techniques?

Use-after-free in network-accessible KDC Proxy Service directly enables unauthenticated remote code execution (RCE) on Windows, mapping to exploitation of public-facing/remote services for initial access/execution.

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

NVD Description

Use after free in Windows KDC Proxy Service (KPSSVC) allows an unauthorized attacker to execute code over a network.

Deeper analysisAI

CVE-2025-49735 is a use-after-free vulnerability (CWE-416) in the Windows KDC Proxy Service (KPSSVC), published on 2025-07-08. It affects Windows systems where the KDC Proxy Service is enabled, allowing an unauthorized attacker to execute arbitrary code over a network. The vulnerability has a CVSS v3.1 base score of 8.1 (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating high severity due to its potential for remote code execution with high confidentiality, integrity, and availability impacts.

An unauthenticated attacker (PR:N) can exploit this vulnerability over the network (AV:N) without user interaction (UI:N), though it requires high attack complexity (AC:H). Successful exploitation enables remote code execution on the target system with the privileges of the KDC Proxy Service, potentially leading to full system compromise if chained with other flaws or in certain configurations.

The Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-49735 provides details on mitigation, including available patches and recommended actions for affected Windows versions.

Details

CWE(s)

Affected Products

microsoft
windows server 2012
all versions, r2
microsoft
windows server 2016
≤ 10.0.14393.8148
microsoft
windows server 2019
≤ 10.0.17763.7434
microsoft
windows server 2022
≤ 10.0.20348.3807
microsoft
windows server 2022 23h2
≤ 10.0.25398.1665
microsoft
windows server 2025
≤ 10.0.26100.4349

CVEs Like This One

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CVE-2025-48824Same product: Microsoft Windows Server 2012
CVE-2025-49753Same product: Microsoft Windows Server 2012

References