Medium severity · published Oct 27, 2026
CVE-2026-105946
Out-of-bounds read vulnerability in NTLM authentication handling impacts Qt
New
5.3
CVSS
0.5%
EPSS
No
On KEV
Description
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 39% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
QT
qt · qt
6.8.0 before 6.8.10; 6.9.0 before 6.11.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-105946
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-105946
codereview.qt-project.org
https://codereview.qt-project.org/c/qt/qtbase/+/744448
codereview.qt-project.org
https://codereview.qt-project.org/c/qt/qtbase/+/745457
codereview.qt-project.org
https://codereview.qt-project.org/c/qt/qtbase/+/745464
wiki.qt.io
https://wiki.qt.io/List_of_known_vulnerabilities_in_Qt_products#CVE-2026-105946:
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