Microsoft Windows up to Server 2025 USB Mass Storage Class 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.
9.6$25k-$100k0.00+

Summaryinfo

A vulnerability was found in Microsoft Windows. It has been rated as very critical. Affected by this vulnerability is an unknown functionality of the component USB Mass Storage Class Driver. This manipulation causes buffer overflow. This vulnerability is registered as CVE-2026-68839. Remote exploitation of the attack is possible. No exploit is available. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability classified as very critical was found in Microsoft Windows. Affected by this vulnerability is an unknown function of the component USB Mass Storage Class Driver. The manipulation with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Heap-based buffer overflow in Windows USB Mass Storage Class Driver allows an unauthorized attacker to execute code over a network.

It is possible to read the advisory at msrc.microsoft.com. This vulnerability is known as CVE-2026-68839 since 07/31/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $25k-$100k at the moment (estimation calculated on 09/08/2026).

Applying a patch is able to eliminate this problem.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.6

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (microsoft): 🔒

CVSSv2info

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

Exploitinginfo

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

Physical: No
Local: No
Remote: Yes

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

07/31/2026 CVE reserved
09/08/2026 +39 days Advisory disclosed
09/08/2026 +0 days VulDB entry created
09/08/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2026-68839 (🔒)
GCVE (CVE): GCVE-0-2026-68839
GCVE (VulDB): GCVE-100-400015
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 09/08/2026 19:55
Changes: 09/08/2026 19:55 (63)
Complete: 🔍
Cache ID: 216::103

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