Microsoft Windows up to Server 2025 Remote Access Connection Manager null pointer dereference

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.6$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Microsoft Windows. This affects an unknown function of the component Remote Access Connection Manager. Executing a manipulation can lead to null pointer dereference. This vulnerability appears as CVE-2026-21525. The attack requires local access. In addition, an exploit is available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability has been found in Microsoft Windows and classified as problematic. This vulnerability affects some unknown functionality of the component Remote Access Connection Manager. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. CVE summarizes:

Null pointer dereference in Windows Remote Access Connection Manager allows an unauthorized attacker to deny service locally.

The weakness was presented 02/10/2026 as confirmed security update guide (Website). The advisory is available at msrc.microsoft.com. This vulnerability was named CVE-2026-21525. The exploitation appears to be easy. Local access is required to approach this attack. Technical details are unknown but an exploit is available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 03/27/2026).

It is declared as attacked. This issue was added on 02/10/2026 to the CISA Known Exploited Vulnerabilities Catalog with a due date of 03/03/2026:

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

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 Zero-Day.cz (1073). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 5.6

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 6.2
Vendor Vector (Microsoft): 🔒

CNA Base Score: 6.2
CNA Vector (Microsoft): 🔒

CVSSv2info

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

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Attacked

EPSS Score: 🔒
EPSS Percentile: 🔒

KEV Added: 🔒
KEV Due: 🔒
KEV Remediation: 🔒
KEV Ransomware: 🔒
KEV Notice: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Zero-Day.cz: 🔒

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Timelineinfo

02/10/2026 VulDB entry created
02/10/2026 +0 days Advisory disclosed
02/10/2026 +0 days Countermeasure disclosed
03/27/2026 +45 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2026-21525 (🔒)
GCVE (CVE): GCVE-0-2026-21525
GCVE (VulDB): GCVE-100-345298
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 02/10/2026 19:35
Updated: 03/27/2026 22:30
Changes: 02/10/2026 19:35 (35), 02/10/2026 19:38 (34), 02/11/2026 00:02 (17), 02/11/2026 18:02 (12), 03/18/2026 09:14 (2), 03/27/2026 22:30 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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