Description
An issue was found in the private API function qDecodeDataUrl() in QtCore, which is used in QTextDocument and QNetworkReply, and, potentially, in user code. If the function was called with malformed data, for example, an URL that contained a "charset" parameter that lacked a value (such as "data:charset,"), and Qt was built with assertions enabled, then it would hit an assertion, resulting in a denial of service (abort). This impacts Qt up to 5.15.18, 6.0.0->6.5.8, 6.6.0->6.8.3 and 6.9.0. This has been fixed in 5.15.19, 6.5.9, 6.8.4 and 6.9.1.
References (1)
Core 1
Core References
Various Sources
https://codereview.qt-project.org/c/qt/qtbase/+/642006
Scores
CVSS v4
8.4
EPSS
0.0031
EPSS Percentile
22.3%
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:H/SC:N/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:U/V:X/RE:M/U:Clear
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-20
Status
published
Products (7)
The Qt Company/Qt
< 5.15.18
The Qt Company/Qt
6.0.0 - 6.5.8
The Qt Company/Qt
6.5.9
The Qt Company/Qt
6.6.0 - 6.8.3
The Qt Company/Qt
6.8.4
The Qt Company/Qt
6.9.0
The Qt Company/Qt
6.9.1
Published
Jun 02, 2025
Tracked Since
Feb 18, 2026