An out-of-bounds read vulnerability in the Qt CoAP message parsing (QCoapInternalReply::createFromFrame()) of the Qt CoAP module. Processing a malformed CoAP message can cause an application using Qt CoAP to crash (loss of availability) or to continue operating on incorrect data (potential loss of integrity).

A memory corruption vulnerability in the QMqttClient class of the Qt MQTT module. Under certain MQTT 5 connection settings between client and server, QMqttClient may corrupt memory, which can cause the application to crash.

An out-of-bounds write vulnerability in the Qt QTextCodec iconv-based encoding of the Qt 5 Compatibility APIs module (Qt Core in Qt 5 and earlier) impacts Qt. Under certain conditions, encoding text with QTextCodec may write outside an internal buffer. This can cause the application to crash and may affect data integrity.

An out-of-bounds read vulnerability in the QTextCodec TSCII encoding of the Qt 5 Compatibility APIs module (Qt Core in Qt 5 and earlier) impacts Qt. Applications that convert text to the TSCII encoding through QTextCodec may read memory outside the input buffer, which can cause the application to crash or misinterpret the data.

A malicious or compromised HTTP/2 server withholding SETTINGS ACK can send RSTSTREAM on a completed stream, planting a null pointer, and then send a PUSHPROMISE for that stream, causing a null pointer dereference in the QNetworkAccessManager class of the Qt Network module that crashes the application.

Specially crafted CBOR input passed to QCborValue::fromCbor() in Qt Core can cause an out-of-bounds read, which may crash the application and could expose information.

A use-after-free vulnerability in the Qt QNetworkAccessManager HTTP/2 client support of the Qt Network module allows a malicious or compromised HTTP/2 server to cause the client application to crash, affecting availability.

An attacker able to supply a crafted XML document to an application using QXmlStreamReader can cause disproportionate CPU consumption during parsing, making the application unresponsive (denial of service). Exploitation requires only that the application parse attacker-influenced XML; no authentication, privileges, or user interaction beyond ingesting the input are needed. There is no loss of confidentiality or integrity — no data disclosure, data modification, or code execution — and the impact is contained to the affected process.

A malicious SVG can trigger an integer overflow which in turn triggers a null-pointer dereference in VectorImage QML Type.

A malformed header in the binary file fed to QBinaryJson::fromBinaryData() can cause undefined behaviour because of out-of-bounds read.

A defect in the Qt for MCUs core string handling causes heap memory corruption. When an application passes text into Qt Quick Ultralite using the public Qul::String interface type, and that text is held in a std::string, the conversion to the internal string type copies the pointer without taking ownership of it. Two objects then release the same memory, producing a double free, an invalid free, or a use-after-free.

In Qt for MCUs, a Text element that displays styled text halts the device if an <img> tag in the text contains an attribute with an empty value. The text parser passes the empty value to an internal check that only accepts non-empty values. The check fails and reports an error, and the default error handler halts the device.

Strings optimized for Latin-1 displaying Latin-1 characters cause incorrect String.arg() formatting by an incorrect buffer size calculation, causing out-of-bounds reading.

Authentication bypass vulnerability in the password authentication mechanism of the Qt VNC Server module. An attacker using a specially modified VNC client that violates the RFB protocol can bypass Qt VNC Server's password authentication and gain unauthorized remote access to the shared application, compromising the confidentiality and integrity of the session.

Out-of-bounds read vulnerability in Context2D.path and PathSvg.path properties impacts Qt Quick

QDomDocument XML parsing is vulnerable to a remotely-triggerable denial-of-service crash when processing untrusted input.

QDomDocument XML parsing is vulnerable to a remotely-triggerable denial-of-service crash when processing untrusted input.

An out-of-bounds read in Qt NFC's language code length parsing allows a physically proximate attacker to cause a denial of service or limited memory disclosure via a crafted NFC tag.

Uncontrolled recursion in Qt's QDomDocument serialization (QtXml) lets deeply nested untrusted XML crash the app via stack exhaustion (DoS only).

Uncontrolled recursion (CWE-674) in the QDomDocument/QDomNode serialization path of the Qt XML module (QtXml, qtbase). QDomElementPrivate::save() and QDomNodePrivate::save() recurse mutually, consuming one stack frame per level of element nesting with no depth limit, no configurable bound and no error return. A document with deeply nested elements parses successfully but exhausts the call stack and terminates the process when serialized. Reachable via QDomDocument::toByteArray() (Qt 4.0 and later), QDomDocument::toString(), QDomDocument::toCString(), QDomNode::save(), and operator<<(QTextStream&, const QDomNode&). Denial of service only — no code execution and no memory disclosure.

Improper output neutralization (XML injection) in QDom comment, CDATA, and processing-instruction serialization in Qt XML from 4.0.0 through 6.11 allows untrusted text serialized by an application into those nodes to inject arbitrary XML markup, because the node terminators are not escaped under the default InvalidDataPolicy (AcceptInvalidChars). Fixed in Qt 6.12.

An out-of-bounds read (buffer over-read) vulnerability exists in QTextCodec::codecForName() in Qt. When the function is called with a QByteArray that is not NUL-terminated (for example, one created with QByteArray::fromRawData()), the codec-name matching routine reads past the end of the supplied buffer. In most cases this results in an incorrect text codec being selected; in the worst case, if the over-read reaches unmapped memory, the process crashes (denial of service). The over-read is bounded by the length of the longest codec-name candidate, and the out-of-bounds bytes are only compared internally against Qt's fixed list of codec names, so no data is disclosed to an attacker. Applications that do not pass non-NUL-terminated QByteArrays to QTextCodec::codecForName() are not exposed. The affected code resides in the Qt5Compat module from Qt 6.0.0 onward, and in Qt Core (qtbase) in Qt 4.x and Qt 5.x.

A type confusion vulnerability in Qt SVG allows an attacker to cause an application crash via a crafted SVG image.

When processing SVG marker references, the renderer retrieves a node by its id attribute and casts it to QSvgMarker without verifying the node type. A non-marker element (such as a <line> element) that references itself as a marker triggers an out-of-bounds heap read due to the object size difference between QSvgLine and QSvgMarker, followed by an endless recursion that bypasses the marker recursion guard through incorrect virtual dispatch. The result is an application crash (denial of service).

This issue affects Qt SVG:  from 6.7.0 before 6.8.8, from 6.9.0 before 6.11.1.

Insufficient validation of node IDs in Qt SVG module allows arbitrary QML/JavaScript code injection when loading malicious SVG files through the VectorImage component in Qt Quick. While QML execution is typically more restricted than native code execution, this could still lead to denial of service, information disclosure, or other impacts depending on the application's privilege level and data access.

Insufficient validation of node IDs in Qt SVG module allows arbitrary QML/JavaScript code injection when loading malicious SVG files through the VectorImage component in Qt Quick. While QML execution is typically more restricted than native code execution, this could still lead to denial of service, information disclosure, or other impacts depending on the application's privilege level and data access.

QLowEnergyController in Qt before 6.8.2 mishandles malformed Bluetooth ATT commands, leading to an out-of-bounds read (or division by zero). This is fixed in 5.15.19, 6.5.9, and 6.8.2.

There is an incomplete cleanup vulnerability in Qt Network's Schannel support on Windows which can lead to a Denial of Service over a long period.

This issue affects Qt from 5.15.0 through 6.8.3, from 6.9.0 before 6.9.2.

The module will parse a <pattern> node which is not a child of a structural node. The node will be deleted after creation but might be accessed later leading to a use after free.

Uncontrolled recursion in Qt SVG module

When passing values outside of the expected range to QColorTransferGenericFunction it can cause a denial of service, for example, this can happen when passing a specifically crafted ICC profile to QColorSpace::fromICCProfile. This issue affects Qt from 6.6.0 through 6.8.3, from 6.9.0 through 6.9.1. This is fixed in 6.8.4 and 6.9.2.