Ubuntu Security Notices USN-8025-1 USN-8025-1: .NET vulnerability Publication date 11 February 2026 Overview .NET could be made to bypass security features. Releases 25.10 22.04 LTS Packages dotnet10 - .NET CLI tools and runtime dotnet8 - .NET CLI tools and runtime dotnet9 - .NET CLI tools and runtime Details Kevin Jones discovered that the System.Security.Cryptography.Cose component in .NET did not properly handle certain missing special elements in input data. An attacker could possibly use this issue to bypass security checks and gain unauthorized access or perform data manipulation. Kevin Jones discovered that the System.Security.Cryptography.Cose component in .NET did not properly handle certain missing special elements in input data. An attacker could possibly use this issue to bypass security checks and gain unauthorized access or perform data manipulation. Update instructions In general, a standard system update will make all the necessary changes. Learn more about how to get the fixes. The problem can be corrected by updating your system to the following package versions: Ubuntu Release Package Version 25.10 questing aspnetcore-runtime-10.0 – 10.0.3-0ubuntu1~25.10.1 aspnetcore-runtime-8.0 – 8.0.24-0ubuntu1~25.10.1 aspnetcore-runtime-9.0 – 9.0.13-0ubuntu1~25.10.1 dotnet-host-10.0 – 10.0.3-0ubuntu1~25.10.1 dotnet-host-8.0 – 8.0.24-0ubuntu1~25.10.1 dotnet-host-9.0 – 9.0.13-0ubuntu1~25.10.1 dotnet-hostfxr-10.0 – 10.0.3-0ubuntu1~25.10.1 dotnet-hostfxr-8.0 – 8.0.24-0ubuntu1~25.10.1 dotnet-hostfxr-9.0 – 9.0.13-0ubuntu1~25.10.1 dotnet-runtime-10.0 – 10.0.3-0ubuntu1~25.10.1 dotnet-runtime-8.0 – 8.0.24-0ubuntu1~25.10.1 dotnet-runtime-9.0 – 9.0.13-0ubuntu1~25.10.1 dotnet-sdk-10.0 – 10.0.103-0ubuntu1~25.10.1 dotnet-sdk-8.0 – 8.0.124-0ubuntu1~25.10.1 dotnet-sdk-9.0 – 9.0.114-0ubuntu1~25.10.1 dotnet-sdk-aot-10.0 – 10.0.103-0ubuntu1~25.10.1 dotnet-sdk-aot-9.0 – 9.0.114-0ubuntu1~25.10.1 dotnet10 – 10.0.103-10.0.3-0ubuntu1~25.10.1 dotnet8 – 8.0.124-8.0.24-0ubuntu1~25.10.1 dotnet9 – 9.0.114-9.0.13-0ubuntu1~25.10.1 22.04 LTS jammy aspnetcore-runtime-8.0 – 8.0.24-0ubuntu1~22.04.1 dotnet-host-8.0 – 8.0.24-0ubuntu1~22.04.1 dotnet-hostfxr-8.0 – 8.0.24-0ubuntu1~22.04.1 dotnet-runtime-8.0 – 8.0.24-0ubuntu1~22.04.1 dotnet-sdk-8.0 – 8.0.124-0ubuntu1~22.04.1 dotnet8 – 8.0.124-8.0.24-0ubuntu1~22.04.1 Reduce your security exposure Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines. Get Ubuntu Pro References CVE-2026-21218 CVE-2026-21218