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USN-8420-1: .NET vulnerabilities

USN-8420-1: .NET vulnerabilities

Ubuntu June 11, 2026

It was discovered that .NET did not properly handle link resolution before file access. A local attacker could use this issue to perform unauthorized file tampering and write arbitrary files outside of the intended extraction directory. ( CVE-2026-45491 ) It was discovered that .NET did not properly handle deeply-nested MessagePack arrays. An attacker could use this to cause .NET to consume excessive resources, resulting in a denial of service. ( CVE-2026-45591 )

It was discovered that .NET did not properly handle link resolution before file access. A local attacker could use this issue to perform unauthorized file tampering and write arbitrary files outside of the intended extraction directory. ( CVE-2026-45491 )

It was discovered that .NET did not properly handle deeply-nested MessagePack arrays. An attacker could use this to cause .NET to consume excessive resources, resulting in a denial of service. ( CVE-2026-45591 )

It was discovered that .NET did not properly handle link resolution before file access. A local attacker could use this issue to perform unauthorized file tampering and write arbitrary files outside of the intended extraction directory. ( CVE-2026-45491 ) It was discovered that .NET did not properly handle deeply-nested MessagePack arrays. An attacker could use this to cause .NET to consume excessive resources, resulting in a denial of service. ( CVE-2026-45591 )

It was discovered that .NET did not properly handle link resolution before file access. A local attacker could use this issue to perform unauthorized file tampering and write arbitrary files outside of the intended extraction directory. ( CVE-2026-45491 )

It was discovered that .NET did not properly handle deeply-nested MessagePack arrays. An attacker could use this to cause .NET to consume excessive resources, resulting in a denial of service. ( CVE-2026-45591 )

In general, a standard system update will make all the necessary changes.

The problem can be corrected by updating your system to the following package versions:

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Extracted Entities

Attack Types (2)

CWE Weaknesses (1)

Platforms (1)