.NET Elevation of Privilege Vulnerability
Date: 2026-03
Affected: nuget/Microsoft.NetCore.App.Runtime.linux-x64, nuget/Microsoft.NetCore.App.Runtime.linux-musl-x64, nuget/Microsoft.NetCore.App.Runtime.linux-musl-arm64
Attack vector: auth-bypass
Category: vulnerability-disclosure
Severity: High
CVE: CVE-2026-26131
CWE: CWE-276
CVSS: 7.8 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)

# Microsoft Security Advisory CVE-2026-26131 – .NET Elevation of Privilege Vulnerability ## Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 10.0. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. An elevation of privilege vulnerability exists in .NET due to improper authorization. Incorrect packaging permissions could allow an attacker to gain elevated privileges. ## Announcement Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/386 ## CVSS Details - **Severity:** High - **Version:** 3.1 - **Score:** 7.8 - **Vector:** `CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C` - **Weakness:** CWE-276 (Incorrect Default Permissions) ## Affected Platforms - **Platforms:** Linux - **Architectures:** All ## Affected Products ### <a name=".NET 10"></a>.NET 10 Package name | Affected version | Patched version ------------ | ---------------- | ------------------------- [Microsoft.NetCore.App.Runtime.linux-arm](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.linux-arm) | >= 10.0.0, <= 10.0.3 | 10.0.4 [Microsoft.NetCore.App.Runtime.linux-arm64](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.linux-arm64) | >= 10.0.0, <= 10.0.3 | 10.0.4 [Microsoft.NetCore.App.Runtime.linux-musl-arm](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.li


Mitigations:

Architectural layers (MAESTRO):