---
id: CVE-2026-105946
title: Out-of-bounds read vulnerability in NTLM authentication handling impacts Qt
summary: >-
  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)…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N/E:P'
cvssSource: cna
cwe:
  - CWE-125
vendor: qt
product: qt
affected:
  - qt >= 6.8.0 < 6.8.10
  - qt >= 6.9.0 < 6.11.2
published: '2026-10-27'
updated: '2026-10-27'
sourceUpdated: '2026-10-27T06:45:36.400Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-105946'
references:
  - url: >-
      https://wiki.qt.io/List_of_known_vulnerabilities_in_Qt_products#CVE-2026-105946:
  - url: 'https://codereview.qt-project.org/c/qt/qtbase/+/745457'
  - url: 'https://codereview.qt-project.org/c/qt/qtbase/+/744448'
  - url: 'https://codereview.qt-project.org/c/qt/qtbase/+/745464'
tags:
  - cve.org
epss: 0.00455
epssPercentile: 0.39292
ingestedAt: '2026-10-27T16:11:59.227Z'
---

## Overview

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

- `qt >= 6.8.0 < 6.8.10`
- `qt >= 6.9.0 < 6.11.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.