CVE-2026-70174: Microsoft .net Framework 3.5

High severity, CVSS 8.8. EPSS: 0.8% chance of exploitation in the next 30 days.

Improperly implemented security check for standard in .NET allows an unauthorized attacker to execute code over a network.

Affected products

• Microsoft Microsoft .net Framework 3.5
• Microsoft Microsoft .net Framework 3.5 And 4.6.2/4.7/4.7.1/4.7.2
• Microsoft Microsoft .net Framework 3.5 And 4.7.2
• Microsoft Microsoft .net Framework 3.5 And 4.8
• Microsoft Microsoft .net Framework 3.5 And 4.8.1
• Microsoft Microsoft .net Framework 4.6.2/4.7/4.7.1/4.7.2: from 4.7.0, before 4.7.4150.0 (fixed in 4.7.4150.0)
• Microsoft Microsoft .net Framework 4.8: from 4.8.0, before 4.8.4811.0 (fixed in 4.8.4811.0)
• Microsoft Microsoft .net Framework 4.8.1: from 4.8.0.0, before 4.8.9363.0 (fixed in 4.8.9363.0)
• Microsoft Microsoft Visual Studio 2022 Version 17.14: from 17.14.0, before 17.14.42 (fixed in 17.14.42)
• Microsoft Microsoft Visual Studio 2026 Version 18.10: from 18.10.0, before 18.10.4 (fixed in 18.10.4)
• Microsoft Net 10.0: from 10.0.0, before 10.0.13 (fixed in 10.0.13)
• Microsoft Net 11.0: from 11.0.0, before 11.0.0-rc.2 (fixed in 11.0.0-rc.2)
• Microsoft Net 8.0: from 8.0.0, before 8.0.32 (fixed in 8.0.32)
• Microsoft Net 9.0: from 9.0.0, before 9.0.21 (fixed in 9.0.21)

Affected packages

• Microsoft.WindowsDesktop.App.Runtime.win-arm64 (NuGet)
• Microsoft.WindowsDesktop.App.Runtime.win-x64 (NuGet)
• Microsoft.WindowsDesktop.App.Runtime.win-x86 (NuGet)

Published 2026-10-13. Last modified 2026-10-14.