---
id: CVE-2026-94370
title: A defect in the Qt for MCUs core string handling causes heap memory corruption
summary: >-
  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 t…
severity: none
cwe:
  - CWE-415
  - CWE-416
  - CWE-590
  - CWE-665
published: '2026-10-14'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T06:17:07.070'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-94370'
references:
  - url: >-
      https://wiki.qt.io/List_of_known_vulnerabilities_in_Qt_products#CVE-2026-94370:
    label: a59d8014-47c4-4630-ab43-e1b13cbe58e3
tags:
  - nvd
ingestedAt: '2026-10-14T07:21:04.831Z'
---

## Overview

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.

## Remediation

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