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TI-2025-05412 Aliases CVE-2025-5991GHSA-xv5c-vg59-hj7x

Use after free in QHttp2ProtocolHandler

Priority LOW 10CWE-416Published · Updated

Key facts

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

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

Summary

There is a "Use After Free" vulnerability in Qt's QHttp2ProtocolHandler in the QtNetwork module. This only affects HTTP/2 handling, HTTP handling is not affected by this at all. This happens due to a race condition between how QHttp2Stream uploads the body of a POST request and the simultaneous handling of HTTP error responses. This issue only affects Qt 6.9.0 and has been fixed for Qt 6.9.1.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00142 3rd percentileScored 2026-11-07
Fix Fixed Qt (Qt): 6.9.1

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
qtQt6.9.06.9.1Patch availableCNA
  • Qt Vendorqt Affected 6.9.0 Fixed in 6.9.1 Patch available CNA

Remediation

  • Fix · CNA Qt (Qt) Fixed in 6.9.1

Vendor assessments

Red Hat

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

Not affected: 5 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

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-5991
  2. 2026-10-03 Alias added: GHSA-xv5c-vg59-hj7x

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

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences