Ubuntu 22.04 LTS / 24.04 LTS / 26.04 LTS : .NET vulnerabilities (USN-8553-1)

high Nessus Plugin ID 327336

Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

The remote Ubuntu 22.04 LTS / 24.04 LTS / 26.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8553-1 advisory.

Artur Stetsko discovered that the .NET did not properly validate authentication data. An attacker could possibly use this issue to elevate privileges. (CVE-2026-47300)

Levi Broderick discovered that .NET did not properly handle XML encryption during parsing. An attacker could possibly use this issue to consume excessive resources, resulting in a denial of service.
(CVE-2026-47302)

Pham Quang Minh discovered that .NET did not properly parse authentication data. An attacker could possibly use this issue to bypass authentication and elevate privileges. (CVE-2026-47303)

Levi Broderick discovered that .NET did not properly verify cryptographic signatures during XML encryption. An attacker could possibly use this issue to bypass security features over a network and access encrypted data. (CVE-2026-47304)

It was discovered that .NET did not properly validate input during TLS handshakes. An attacker could possibly use this issue to cause .NET to crash, resulting in a denial of service. (CVE-2026-50524)

Levi Broderick discovered that .NET did not properly handle resource allocation during XML encryption. An attacker could possibly use this issue to consume excessive resources, resulting in a denial of service.
(CVE-2026-50525)

Siwei Li discovered that .NET did not properly handle link resolution before file access during the container image build process. A local attacker could possibly use this issue to inject resources that could be incorporated into container images built by other users on the same machine. (CVE-2026-50526)

Levi Broderick discovered that .NET did not properly handle memory while performing XML encryption. An attacker could possibly use this issue to cause .NET to crash, resulting in a denial of service.
(CVE-2026-50527)

Henrique Pereira discovered that .NET did not properly handle authorization checks during TLS/SSL connections. An attacker could possibly use this issue to bypass authorization checks during secure communications. (CVE-2026-50528)

It was discovered that .NET did not properly handle resource allocation during XML encryption. An attacker could possibly use this issue to consume excessive resources, resulting in a denial of service.
(CVE-2026-50648)

Miha Zupan discovered that .NET did not properly limit resource allocation when handling HTTP/2 requests.
An attacker could possibly use this issue to consume excessive resources, resulting in a denial of service. (CVE-2026-50651)

It was discovered that the .NET SMTP client did not properly handle the encoding or escaping of output. An attacker could possibly use this issue to spoof messages during message routing. (CVE-2026-50659)

It was discovered that .NET did not properly validate resource types when parsing X.509 certificates. An attacker could possibly use this issue to cause .NET to crash, resulting in a denial of service.
(CVE-2026-57108)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

https://ubuntu.com/security/notices/USN-8553-1

Plugin Details

Severity: High

ID: 327336

File Name: ubuntu_USN-8553-1.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 7/16/2026

Updated: 7/16/2026

Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.12

CVSS v2

Risk Factor: High

Base Score: 9

Temporal Score: 6.7

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C

CVSS Score Source: CVE-2026-47303

CVSS v3

Risk Factor: High

Base Score: 8.8

Temporal Score: 7.7

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:dotnet-sdk-8.0-source-built-artifacts, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:dotnet-host-8.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-sdk-10.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-runtime-10.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-sdk-dbg-10.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-sdk-8.0, p-cpe:/a:canonical:ubuntu_linux:aspnetcore-runtime-10.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-host-10.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-sdk-aot-10.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-targeting-pack-8.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-runtime-dbg-8.0, p-cpe:/a:canonical:ubuntu_linux:aspnetcore-targeting-pack-10.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-apphost-pack-10.0, p-cpe:/a:canonical:ubuntu_linux:aspnetcore-runtime-8.0, p-cpe:/a:canonical:ubuntu_linux:aspnetcore-targeting-pack-8.0, p-cpe:/a:canonical:ubuntu_linux:dotnet10, p-cpe:/a:canonical:ubuntu_linux:dotnet-apphost-pack-8.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-runtime-8.0, p-cpe:/a:canonical:ubuntu_linux:dotnet8, p-cpe:/a:canonical:ubuntu_linux:netstandard-targeting-pack-2.1-8.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-sdk-dbg-8.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-hostfxr-8.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-runtime-dbg-10.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-sdk-10.0-source-built-artifacts, p-cpe:/a:canonical:ubuntu_linux:dotnet-templates-8.0, cpe:/o:canonical:ubuntu_linux:26.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:dotnet-hostfxr-10.0, p-cpe:/a:canonical:ubuntu_linux:dotnet-targeting-pack-10.0, p-cpe:/a:canonical:ubuntu_linux:aspnetcore-runtime-dbg-10.0, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:dotnet-templates-10.0, p-cpe:/a:canonical:ubuntu_linux:aspnetcore-runtime-dbg-8.0

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 7/15/2026

Vulnerability Publication Date: 7/14/2026

Reference Information

CVE: CVE-2026-47300, CVE-2026-47302, CVE-2026-47303, CVE-2026-47304, CVE-2026-50524, CVE-2026-50525, CVE-2026-50526, CVE-2026-50527, CVE-2026-50528, CVE-2026-50648, CVE-2026-50651, CVE-2026-50659, CVE-2026-57108

USN: 8553-1