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TI-2026-73787 Aliases CVE-2026-94370GHSA-vcv3-3vwp-2j63

Heap memory corruption in Qt for MCUs string handling

Priority LOW 29CWE-415Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
Low · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

Qt for MCUs from 2.12.1 before 2.12.3 contains a memory corruption flaw in its core string handling. When an application passes a std::string into Qt Quick Ultralite through the Qul::String interface, the conversion copies the pointer without taking ownership, so two objects free the same memory (CWE-415). A remote unauthenticated attacker can corrupt heap memory, with high impact on integrity and availability.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00332 26th percentileScored 2026-11-07
Fix Fixed Qt_for_MCUs (qt): 2.12.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
qtQt_for_MCUs2.12.1 to before 2.12.32.12.3Patch availableCNA
  • Qt_for_MCUs Vendorqt Affected 2.12.1 to before 2.12.3 Fixed in 2.12.3 Patch available CNA

Remediation

Update Qt for MCUs to version 2.12.3, which fixes the flaw.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA Qt_for_MCUs (qt) Fixed in 2.12.3

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

Not affected: 6 products
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat Hardened Images

Timeline

  1. 2026-10-14 Threatist record created from CVE-2026-94370
  2. 2026-10-14 Alias added: GHSA-vcv3-3vwp-2j63
  3. 2026-10-14 CISA SSVC decision points changed
  4. 2026-10-14 Priority changed: MEDIUM → LOW
  5. 2026-10-16 Affected versions changed · Red Hat
  6. 2026-10-16 CVSS score added · Red Hat

References

Other 1

  • TI-2024-23902 QAbstractOAuth in Qt Network Authorization in Qt before 5.15.17, 6.x before 6.2.13, 6.3.x… CVSS 3.1CRITICAL 9.8
  • TI-2022-21359 Heap-based buffer overflow in Qt CVSS 3.1HIGH 8.8
  • TI-2022-19524 Integer overflow in Qt CVSS 3.1HIGH 8.8
  • TI-2023-18997 In Qt before 5.15.15, 6.x before 6.2.9, and 6.3.x through 6.5.x before 6.5.2, there can… CVSS 3.1HIGH 7.5
  • TI-2021-09305 Integer Overflow vulnerability in qsvghandler.cpp in Qt qtsvg versions 5.15.1, 6.0.0… CVSS 3.1MEDIUM 5.5
  • TI-2023-28356 An issue was discovered in the HTTP2 implementation in Qt before 5.15.17, 6.x before… CVSS 3.1CRITICAL 9.8
See all 106 →

Sources

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