CVE-2026-69439: CWE-122: Heap-based Buffer Overflow in Microsoft .NET 10.0
Description
CVE-2026-69439 is a heap-based buffer overflow vulnerability in Microsoft .NET 10.0 and related versions. It allows an unauthorized attacker to elevate privileges over a network. The vulnerability affects multiple versions of .NET including 8.0.x, 9.0.x, 10.0.x, 11.0.0, 17.14.x, and 18.9.x. A fix has been officially released by Microsoft.
CVSS v3.1
Score 8.8high
Affected software
Microsoft
.NET 10.0
Microsoft
.NET 11.0
Microsoft
.NET 8.0
Microsoft
.NET 9.0
Microsoft
Microsoft Visual Studio 2022 version 17.14
Microsoft
Microsoft Visual Studio 2026 version 18.9
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CWE-122) is a heap-based buffer overflow in Microsoft .NET and Visual Studio that enables an unauthorized attacker to elevate privileges remotely. It affects several versions of .NET from 8.0.0 up to but not including 8.0.31, 9.0.0 up to but not including 9.0.20, 10.0.0 up to but not including 10.0.12, exactly 10.0.0, 11.0.0, 17.14.0 up to but not including 17.14.40, and 18.9.0 up to but not including 18.9.3. The vulnerability has a high CVSS v3.1 score of 8.8, indicating high impact on confidentiality, integrity, and availability. Microsoft has published an official fix for this vulnerability.
Potential Impact
Successful exploitation allows an unauthorized attacker to elevate privileges over a network, potentially leading to full compromise of affected systems. The vulnerability impacts confidentiality, integrity, and availability at a high level as indicated by the CVSS score of 8.8.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security updates provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69439 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-08-03T20:59:32.784Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-69439","vendor":"Microsoft"}]
Threat ID: 6aa044f8acd9273b49fa8075
Added to database: 09/08/2026, 17:25:12 UTC
Last enriched: 10/16/2026, 20:40:46 UTC
Last updated: 10/23/2026, 15:10:14 UTC
Views: 64
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