Microsoft Windows up to Server 2025 Kernel 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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7.1$5k-$25k0.00

Summaryinfo

A vulnerability was found in Microsoft Windows up to Server 2025 and classified as critical. This issue affects some unknown processing of the component Kernel. Executing a manipulation can lead to heap-based overflow. This vulnerability is handled as CVE-2026-33841. It is possible to launch the attack on the local host. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Microsoft Windows up to Server 2025 and classified as critical. This vulnerability affects an unknown code of the component Kernel. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is 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(). As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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

The weakness was released 05/12/2026 as confirmed security update guide (Website). The advisory is shared for download at msrc.microsoft.com. This vulnerability was named CVE-2026-33841. The exploitation appears to be easy. The attack needs to be approached locally. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 06/21/2026).

Upgrading to version 10.0.20348.5074 or 10.0.20348.5139 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-1489). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Microsoft Windows Server 2012
  • Microsoft Windows Server 2012 R2
  • Microsoft Windows Server 2016
  • Microsoft Windows 10
  • Microsoft Windows Server 2019
  • Microsoft Windows Server 2022
  • Microsoft Windows 11
  • Microsoft Windows Server 2025
  • Microsoft Windows Admin Center

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: Heap-based overflow
CWE: CWE-122 / CWE-119
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: Upgrade
Status: 🔍

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

Upgrade: Windows 10.0.20348.5074/10.0.20348.5139

Timelineinfo

05/12/2026 VulDB entry created
05/12/2026 +0 days Advisory disclosed
05/12/2026 +0 days Countermeasure disclosed
06/21/2026 +40 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2026-33841 (🔒)
GCVE (CVE): GCVE-0-2026-33841
GCVE (VulDB): GCVE-100-363136
CERT Bund: WID-SEC-2026-1489 - Microsoft Windows Produkte: Mehrere Schwachstellen

scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 05/12/2026 19:18
Updated: 06/21/2026 16:29
Changes: 05/12/2026 19:18 (38), 05/12/2026 19:21 (32), 05/15/2026 07:46 (6), 06/21/2026 16:29 (11)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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