CVE-2026-42899 · cross-distro fix matrix

CVE-2026-42899: Muhammad Abdul Rehman discovered that .NET incorrectly handled certain

Affects 3 Linux releases across 50 (distro × package) combinations. First disclosed: 2026-05-12.

CVSS v3:HIGH · 7.5(NVD-published)

Fix per ecosystem

Each block below is a distro release where CVE-2026-42899 has a known fix. Run the listed command on that distro to remediate.

Ubuntu jammy

Source: Ubuntu USN

dotnet8→ fixed in8.0.127-8.0.27-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet8
```
aspnetcore-runtime-8.0→ fixed in8.0.27-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y aspnetcore-runtime-8.0
```
aspnetcore-runtime-dbg-8.0→ fixed in8.0.27-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y aspnetcore-runtime-dbg-8.0
```
aspnetcore-targeting-pack-8.0→ fixed in8.0.27-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y aspnetcore-targeting-pack-8.0
```
dotnet-apphost-pack-8.0→ fixed in8.0.27-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-apphost-pack-8.0
```
dotnet-host-8.0→ fixed in8.0.27-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-host-8.0
```
dotnet-hostfxr-8.0→ fixed in8.0.27-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-hostfxr-8.0
```
dotnet-runtime-8.0→ fixed in8.0.27-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-runtime-8.0
```
dotnet-runtime-dbg-8.0→ fixed in8.0.27-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-runtime-dbg-8.0
```
dotnet-sdk-8.0→ fixed in8.0.127-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-sdk-8.0
```
dotnet-sdk-8.0-source-built-artifacts→ fixed in8.0.127-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-sdk-8.0-source-built-artifacts
```
dotnet-sdk-dbg-8.0→ fixed in8.0.127-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-sdk-dbg-8.0
```
dotnet-targeting-pack-8.0→ fixed in8.0.27-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-targeting-pack-8.0
```
dotnet-templates-8.0→ fixed in8.0.127-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-templates-8.0
```
netstandard-targeting-pack-2.1-8.0→ fixed in8.0.127-0ubuntu1~22.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y netstandard-targeting-pack-2.1-8.0
```

Ubuntu noble

Source: Ubuntu USN

dotnet10→ fixed in10.0.108-10.0.8-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet10
```
dotnet8→ fixed in8.0.127-8.0.27-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet8
```
aspnetcore-runtime-10.0→ fixed in10.0.8-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y aspnetcore-runtime-10.0
```
aspnetcore-runtime-8.0→ fixed in8.0.27-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y aspnetcore-runtime-8.0
```
aspnetcore-runtime-dbg-10.0→ fixed in10.0.8-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y aspnetcore-runtime-dbg-10.0
```
aspnetcore-runtime-dbg-8.0→ fixed in8.0.27-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y aspnetcore-runtime-dbg-8.0
```
aspnetcore-targeting-pack-10.0→ fixed in10.0.8-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y aspnetcore-targeting-pack-10.0
```
aspnetcore-targeting-pack-8.0→ fixed in8.0.27-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y aspnetcore-targeting-pack-8.0
```
dotnet-apphost-pack-10.0→ fixed in10.0.8-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-apphost-pack-10.0
```
dotnet-apphost-pack-8.0→ fixed in8.0.27-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-apphost-pack-8.0
```
dotnet-host-10.0→ fixed in10.0.8-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-host-10.0
```
dotnet-host-8.0→ fixed in8.0.27-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-host-8.0
```
dotnet-hostfxr-10.0→ fixed in10.0.8-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-hostfxr-10.0
```
dotnet-hostfxr-8.0→ fixed in8.0.27-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-hostfxr-8.0
```
dotnet-runtime-10.0→ fixed in10.0.8-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-runtime-10.0
```
dotnet-runtime-8.0→ fixed in8.0.27-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-runtime-8.0
```
dotnet-runtime-dbg-10.0→ fixed in10.0.8-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-runtime-dbg-10.0
```
dotnet-runtime-dbg-8.0→ fixed in8.0.27-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-runtime-dbg-8.0
```
dotnet-sdk-10.0→ fixed in10.0.108-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-sdk-10.0
```
dotnet-sdk-10.0-source-built-artifacts→ fixed in10.0.108-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-sdk-10.0-source-built-artifacts
```
dotnet-sdk-8.0→ fixed in8.0.127-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-sdk-8.0
```
dotnet-sdk-8.0-source-built-artifacts→ fixed in8.0.127-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-sdk-8.0-source-built-artifacts
```
dotnet-sdk-aot-10.0→ fixed in10.0.108-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-sdk-aot-10.0
```
dotnet-sdk-dbg-10.0→ fixed in10.0.108-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-sdk-dbg-10.0
```
dotnet-sdk-dbg-8.0→ fixed in8.0.127-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-sdk-dbg-8.0
```
dotnet-targeting-pack-10.0→ fixed in10.0.8-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-targeting-pack-10.0
```
dotnet-targeting-pack-8.0→ fixed in8.0.27-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-targeting-pack-8.0
```
dotnet-templates-10.0→ fixed in10.0.108-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-templates-10.0
```
dotnet-templates-8.0→ fixed in8.0.127-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet-templates-8.0
```
netstandard-targeting-pack-2.1-8.0→ fixed in8.0.127-0ubuntu1~24.04.1USN-8298-1
```
sudo apt-get install --only-upgrade -y netstandard-targeting-pack-2.1-8.0
```

Ubuntu questing

Source: Ubuntu USN

dotnet10→ fixed in10.0.108-10.0.8-0ubuntu1~25.10.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet10
```
dotnet8→ fixed in8.0.127-8.0.27-0ubuntu1~25.10.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet8
```
dotnet9→ fixed in9.0.117-9.0.16-0ubuntu1~25.10.1USN-8298-1
```
sudo apt-get install --only-upgrade -y dotnet9
```
aspnetcore-runtime-10.0→ fixed in10.0.8-0ubuntu1~25.10.1USN-8298-1
```
sudo apt-get install --only-upgrade -y aspnetcore-runtime-10.0
```
aspnetcore-runtime-8.0→ fixed in8.0.27-0ubuntu1~25.10.1USN-8298-1
```
sudo apt-get install --only-upgrade -y aspnetcore-runtime-8.0
```

Are YOU affected by CVE-2026-42899?

5-second check on your actual server. Reads /etc/os-release, uname -r, and the distro's package manager; matches against this same cross-source index live.

curl https://mindsparkstack.com/scan.sh | bash

Form-based quickscan View on NVD

Continuous monitoring beats manual checking

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