Improper handling of highly compressed data in Microsoft products - CVE-2026-69304

Vulnerability identifier: #VU147576

CSH Severity: Medium

CVSS v4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-69304

CWE-ID: CWE-409

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper handling of highly compressed data (data amplification) in ASP.NET Core when processing highly compressed data. A remote attacker can send highly compressed data to cause a denial of service.

.NET
Visual Studio
ASP.NET Core
Microsoft .NET Framework
Fedora
dotnet8.0
dotnet9.0
dotnet10.0

Install security update from vendor's website.

.NET - addressed in versions 8.0.31, 9.0.20
Visual Studio - update to 17.14.40
ASP.NET Core - addressed in versions 8.0.31, 9.0.20
Microsoft .NET Framework - update to 10.0.12
dotnet8.0 - addressed in versions 8.0.131-1.fc43, 8.0.131-1.fc44
dotnet9.0 - addressed in versions 9.0.121-1.fc43, 9.0.121-1.fc44
dotnet10.0 - addressed in versions 10.0.112-1.fc43, 10.0.112-1.fc44, 10.0.112-1.fc45

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-69304

• Multiple vulnerabilities in Visual Studio
• Fedora 45 update for dotnet10.0
• Fedora 44 update for dotnet9.0
• Fedora 43 update for dotnet10.0
• Fedora 44 update for dotnet10.0
• Fedora 43 update for dotnet9.0
• Fedora 43 update for dotnet8.0
• Fedora 44 update for dotnet8.0