VDB-323272 · CVE-2025-54109 · EUVD-2025-27309

Microsoft Windows up to Server 2025 Defender Firewall Service type confusion

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.1	$5k-$25k	0.00

Summaryinfo

A vulnerability described as critical has been identified in Microsoft Windows. This issue affects some unknown processing of the component Defender Firewall Service. Executing a manipulation can lead to type confusion. This vulnerability is tracked as CVE-2025-54109. The attack is restricted to local execution. No exploit exists. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability classified as critical was found in Microsoft Windows. This vulnerability affects an unknown code block of the component Defender Firewall Service. The manipulation with an unknown input leads to a type confusion vulnerability. The CWE definition for the vulnerability is CWE-843. The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Access of resource using incompatible type ('type confusion') in Windows Defender Firewall Service allows an authorized attacker to elevate privileges locally.

The weakness was disclosed 09/09/2025 as confirmed security update guide (Website). The advisory is shared for download at msrc.microsoft.com. This vulnerability was named CVE-2025-54109. The exploitation appears to be easy. The attack needs to be approached locally. Additional levels of successful authentication are required for exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 09/20/2025).

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-27309). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Operating System

Vendor

Microsoft

Name

Windows

Version

License

commercial

Website

Vendor: https://www.microsoft.com/
Product: https://www.microsoft.com/en-us/windows

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.7
VulDB Meta Temp Score: 6.1

VulDB Base Score: 6.7
VulDB Temp Score: 5.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 6.7
Vendor Vector (Microsoft): 🔒

CNA Base Score: 6.7
CNA Vector (Microsoft): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Type confusion
CWE: CWE-843
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Unproven

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔒
0-Day Time: 🔒
Exposure Time: 🔒

Timelineinfo

09/09/2025 VulDB entry created
09/09/2025 +0 days Advisory disclosed
09/09/2025 +0 days Countermeasure disclosed
09/20/2025 +10 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2025-54109 (🔒)
GCVE (CVE): GCVE-0-2025-54109
GCVE (VulDB): GCVE-100-323272
EUVD: 🔒
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 09/09/2025 19:29
Updated: 09/20/2025 03:10
Changes: 09/09/2025 19:29 (35), 09/09/2025 19:32 (34), 09/12/2025 05:48 (11), 09/20/2025 03:10 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.