USN-8216-1: .NET vulnerabilities
Publication date
28 April 2026
Overview
Several security issues were fixed in .NET.
Releases
Packages
- dotnet10 - .NET CLI tools and runtime
Details
Ludvig Pedersen discovered that the System.Security.Cryptography.Xml
library in .NET incorrectly handled certain XML inputs. An attacker could
possibly use this issue to consume excessive resources, resulting in a
denial of service. (CVE-2026-33116, CVE-2026-26171)
Ludvig Pedersen and Kevin Jones discovered that the
System.Security.Cryptography.Xml library in .NET incorrectly handled
certain XML inputs. An attacker could possibly use this issue to cause
.NET to crash, resulting in a denial of service. (CVE-2026-32203)
Ludvig Pedersen discovered that the System.Net.Mail component in .NET
incorrectly handled certain inputs. An attacker could possibly use this
issue to perform a network spoofing attack. (CVE-2026-32178)
It was discovered that the...
Ludvig Pedersen discovered that the System.Security.Cryptography.Xml
library in .NET incorrectly handled certain XML inputs. An attacker could
possibly use this issue to consume excessive resources, resulting in a
denial of service. (CVE-2026-33116, CVE-2026-26171)
Ludvig Pedersen and Kevin Jones discovered that the
System.Security.Cryptography.Xml library in .NET incorrectly handled
certain XML inputs. An attacker could possibly use this issue to cause
.NET to crash, resulting in a denial of service. (CVE-2026-32203)
Ludvig Pedersen discovered that the System.Net.Mail component in .NET
incorrectly handled certain inputs. An attacker could possibly use this
issue to perform a network spoofing attack. (CVE-2026-32178)
It was discovered that the Microsoft.AspNetCore.DataProtection library in
.NET did not properly verify cryptographic signatures under certain
conditions. A remote attacker could possibly use this issue to elevate
privileges. (CVE-2026-40372)
Update instructions
After a standard system update, it is recommended to rotate the DataProtection key ring.
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 | ||
|---|---|---|---|
| 26.04 LTS resolute | aspnetcore-runtime-10.0 – 10.0.7-0ubuntu1~26.04.1 | ||
| dotnet-host-10.0 – 10.0.7-0ubuntu1~26.04.1 | |||
| dotnet-hostfxr-10.0 – 10.0.7-0ubuntu1~26.04.1 | |||
| dotnet-runtime-10.0 – 10.0.7-0ubuntu1~26.04.1 | |||
| dotnet-sdk-10.0 – 10.0.107-0ubuntu1~26.04.1 | |||
| dotnet-sdk-aot-10.0 – 10.0.107-0ubuntu1~26.04.1 | |||
| dotnet10 – 10.0.107-10.0.7-0ubuntu1~26.04.1 | |||
Reduce your security exposure
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