Microsoft Windows 11 24H2/11 25H2/11 26H1/Server 2025 Win32K heap-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.1$5k-$25k0.43+

Summaryinfo

A vulnerability has been found in Microsoft Windows 11 24H2/11 25H2/11 26H1/Server 2025 and classified as very critical. Affected is an unknown function of the component Win32K. Performing a manipulation results in heap-based overflow. This vulnerability is cataloged as CVE-2026-69348. The attack must be initiated from a local position. There is no exploit available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability, which was classified as very critical, was found in Microsoft Windows 11 24H2/11 25H2/11 26H1/Server 2025. This affects an unknown part of the component Win32K. The manipulation with an unknown input leads to a heap-based overflow vulnerability. CWE is classifying the issue as CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Heap-based buffer overflow in Windows Win32K allows an authorized attacker to elevate privileges locally.

It is possible to read the advisory at msrc.microsoft.com. This vulnerability is uniquely identified as CVE-2026-69348 since 08/03/2026. 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 09/08/2026).

Applying a patch is able to eliminate this problem.

Statistical analysis made it clear that VulDB provides the best quality 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: 8.3
VulDB Meta Temp Score: 8.1

VulDB Base Score: 8.8
VulDB Temp Score: 8.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.8
CNA Vector (microsoft): 🔒

CVSSv2info

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

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / 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

08/03/2026 CVE reserved
09/08/2026 +36 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-2026-69348 (🔒)
GCVE (CVE): GCVE-0-2026-69348
GCVE (VulDB): GCVE-100-400179

Entryinfo

Created: 09/08/2026 20:51
Changes: 09/08/2026 20:51 (63)
Complete: 🔍
Cache ID: 216::103

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

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