CVE-2026-114148: ASP.NET Core Elevation of Privilege Vulnerability

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-29 · updated 2026-10-31
Weakness: CWE-276

Description

Incorrect default permissions in ASP.NET Core allows an authorized attacker to elevate privileges locally.

Affected products

Microsoft .NET 10.0 installed on Linux: from 10.0.0 before 10.0.403 — fixed in 10.0.403
Microsoft .NET 10.0 installed on Mac OS: from 10.0.0 before 10.0.403 — fixed in 10.0.403
Microsoft .NET 10.0 installed on Windows: from 10.0.0 before 10.0.403 — fixed in 10.0.403
Microsoft .NET 11.0 installed on Linux: from 11.0.0-preview.1 before 11.0.100-rc.3 — fixed in 11.0.100-rc.3
Microsoft .NET 11.0 installed on Mac OS: from 11.0.0-preview.1 before 11.0.100-rc.3 — fixed in 11.0.100-rc.3
Microsoft .NET 11.0 installed on Windows: from 11.0.0-preview.1 before 11.0.100-rc.3 — fixed in 11.0.100-rc.3
Microsoft .NET 8.0 installed on Linux: from 8.0.0 before 8.0.427 — fixed in 8.0.427
Microsoft .NET 8.0 installed on Mac OS: from 8.0.0 before 8.0.427 — fixed in 8.0.427
Microsoft .NET 8.0 installed on Windows: from 8.0.0 before 8.0.427 — fixed in 8.0.427
Microsoft .NET 9.0 installed on Linux: from 9.0.0 before 9.0.320 — fixed in 9.0.320
Microsoft .NET 9.0 installed on Mac OS: from 9.0.0 before 9.0.320 — fixed in 9.0.320
Microsoft .NET 9.0 installed on Windows: from 9.0.0 before 9.0.320 — fixed in 9.0.320
Microsoft .NET source-build Linux tarballs (all archive types): from 8.0.100 before 10.0.403-servicing.26523.112 — fixed in 10.0.403-servicing.26523.112
Microsoft ASP.NET Core runtime and targeting-pack Linux tarballs (Microsoft-published): from 8.0.0 before 9.0.22 — fixed in 9.0.22

How to fix

Upgrade to a fixed version: Microsoft .NET 10.0 installed on Linux 10.0.403; Microsoft .NET 10.0 installed on Mac OS 10.0.403; Microsoft .NET 10.0 installed on Windows 10.0.403; Microsoft .NET 11.0 installed on Linux 11.0.100-rc.3; Microsoft .NET 11.0 installed on Mac OS 11.0.100-rc.3; Microsoft .NET 11.0 installed on Windows 11.0.100-rc.3; Microsoft .NET 8.0 installed on Linux 8.0.427; Microsoft .NET 8.0 installed on Mac OS 8.0.427; Microsoft .NET 8.0 installed on Windows 8.0.427; Microsoft .NET 9.0 installed on Linux 9.0.320; Microsoft .NET 9.0 installed on Mac OS 9.0.320; Microsoft .NET 9.0 installed on Windows 9.0.320. Check the vendor advisory for mitigations.

In the news

CVE-2026-114148 ASP.NET Core Elevation of Privilege Vulnerability

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-114148

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