Microsoft Windows up to Server 2025 Virtual Hard Disk VHD Miniport Driver buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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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.
7.7$5k-$25k0.00+

Summaryinfo

A vulnerability marked as very critical has been reported in Microsoft Windows. This impacts an unknown function of the component Virtual Hard Disk VHD Miniport Driver. The manipulation leads to buffer overflow. This vulnerability is traded as CVE-2026-81355. An attack has to be approached locally. There is no exploit available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability, which was classified as very critical, has been found in Microsoft Windows. This issue affects an unknown code of the component Virtual Hard Disk VHD Miniport Driver. The manipulation with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Heap-based buffer overflow in Virtual Hard Disk (VHD) Miniport Driver allows an authorized attacker to execute code locally.

The advisory is shared at msrc.microsoft.com. The identification of this vulnerability is CVE-2026-81355 since 08/26/2026. The exploitation is known to be easy. An attack has to be approached locally. Additional levels of successful authentication are needed for exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 09/09/2026).

Applying a patch is able to eliminate this problem.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.7

VulDB Base Score: 8.2
VulDB Temp Score: 7.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (microsoft): 🔒

CVSSv2info

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

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/26/2026 CVE reserved
09/09/2026 +14 days Advisory disclosed
09/09/2026 +0 days VulDB entry created
09/09/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2026-81355 (🔒)
GCVE (CVE): GCVE-0-2026-81355
GCVE (VulDB): GCVE-100-401069
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 09/09/2026 03:03
Changes: 09/09/2026 03:03 (63)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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