Microsoft Windows up to Server 2025 Process Activation link following

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.1$5k-$25k0.00

Summaryinfo

A vulnerability has been found in Microsoft Windows and classified as critical. The impacted element is an unknown function of the component Process Activation. Performing a manipulation results in link following. This vulnerability is known as CVE-2025-21204. Attacking locally is a requirement. No exploit is available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability, which was classified as critical, was found in Microsoft Windows. This affects an unknown part of the component Process Activation. The manipulation with an unknown input leads to a link following vulnerability. CWE is classifying the issue as CWE-59. The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally.

The weakness was published 04/08/2025 as confirmed security update guide (Website). It is possible to read the advisory at msrc.microsoft.com. This vulnerability is uniquely identified as CVE-2025-21204. The exploitability is told to be easy. Attacking locally is a requirement. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 06/04/2025).

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-2025-10245). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.1

VulDB Base Score: 7.8
VulDB Temp Score: 6.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.8
Vendor Vector (Microsoft): 🔍

CNA Base Score: 7.8
CNA Vector (Microsoft): 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Link following
CWE: CWE-59
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Timelineinfo

04/08/2025 🔍
04/08/2025 +0 days 🔍
04/08/2025 +0 days 🔍
06/04/2025 +57 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2025-21204 (🔍)
GCVE (CVE): GCVE-0-2025-21204
GCVE (VulDB): GCVE-100-303915
EUVD: 🔍
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 04/08/2025 19:32
Updated: 06/04/2025 21:26
Changes: 04/08/2025 19:32 (35), 04/08/2025 19:36 (34), 05/29/2025 16:38 (12), 06/04/2025 21:26 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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