UBUNTU-CVE-2026-105946: Medium severity ubuntu/qtbase-opensource-src vulnerability

Published Nov 3, 2026
·
Updated

Out-of-bounds read in the QAuthenticator NTLM authentication handling in the Qt Network module in Qt Group Qt allows remote attackers to obtain sensitive information (heap memory contents) or cause a denial of service (application crash) via a crafted NTLM challenge sent by a malicious server or proxy, when an application using QNetworkAccessManager or QTcpSocket authenticates with NTLM.

Affected Software

11 affected components
ubuntu/qtbase-opensource-src*
ubuntu/qtbase-opensource-src*
ubuntu/qtbase-opensource-src*
ubuntu/qt6-base*
ubuntu/qtbase-opensource-src*
ubuntu/qt6-base*
ubuntu/qtbase-opensource-src*
ubuntu/qt6-base*
ubuntu/qtbase-opensource-src*
ubuntu/qt6-base*
ubuntu/qtbase-opensource-src*

Event History

Nov 3, 2026
CVE Published
via OSV·12:00 AM
Data Sourced
via OSV·12:00 AM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

Which applications are exposed to this issue?

Applications using Qt Network's QNetworkAccessManager or QTcpSocket are exposed when they perform NTLM authentication. The affected Ubuntu packages listed are qtbase-opensource-src and qt6-base.

2

What must an attacker control to exploit it?

An attacker needs to provide a crafted NTLM challenge through a malicious server or proxy. Exploitation also requires the application to authenticate using NTLM, and user interaction is required according to the supplied vector.

3

What is the likely impact of successful exploitation?

A successful exploit may disclose sensitive heap-memory contents or crash the application, causing a denial of service.

Contact

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