CVE-2025-21171: CWE-122: Heap-based Buffer Overflow in Microsoft .NET 9.0
.NET Remote Code Execution Vulnerability
AI Analysis
Technical Summary
CVE-2025-21171 is a heap-based buffer overflow vulnerability (CWE-122) in Microsoft .NET 9.0 that allows remote code execution. The vulnerability has been assigned a CVSS v3.1 score of 7.5, indicating high severity. The attack vector is network-based with high attack complexity and requires user interaction. The vulnerability impacts confidentiality, integrity, and availability. Microsoft has published an official fix for this vulnerability, as detailed in their security advisory.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code remotely, potentially leading to full system compromise. The vulnerability affects confidentiality, integrity, and availability of the affected system.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the provided security update for .NET 9.0 as soon as possible. Refer to the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21171 for detailed patching instructions.
CVE-2025-21171: CWE-122: Heap-based Buffer Overflow in Microsoft .NET 9.0
Description
.NET Remote Code Execution Vulnerability
CVSS v3.1
Score 7.5high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2025-21171 is a heap-based buffer overflow vulnerability (CWE-122) in Microsoft .NET 9.0 that allows remote code execution. The vulnerability has been assigned a CVSS v3.1 score of 7.5, indicating high severity. The attack vector is network-based with high attack complexity and requires user interaction. The vulnerability impacts confidentiality, integrity, and availability. Microsoft has published an official fix for this vulnerability, as detailed in their security advisory.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code remotely, potentially leading to full system compromise. The vulnerability affects confidentiality, integrity, and availability of the affected system.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the provided security update for .NET 9.0 as soon as possible. Refer to the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21171 for detailed patching instructions.
Technical Details
- Data Version
- 5.1
- Assigner Short Name
- microsoft
- Date Reserved
- 2024-12-05T21:43:30.760Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21171","vendor":"Microsoft"}]
Threat ID: 68c0bd4c9ed239a66badea40
Added to database: 09/09/2025, 23:50:36 UTC
Last enriched: 06/10/2026, 09:40:37 UTC
Last updated: 09/10/2026, 19:36:49 UTC
Views: 148
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