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TI-2025-05739 Aliases CVE-2025-6338GHSA-m4hj-jpxf-jhjp

Possible denial of service with multiple incoming connections to a Schannel based server with a TLS backend

Priority MEDIUM 46CWE-459Published · Updated

Key facts

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

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

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00427 37th percentileScored 2026-11-07
Fix Fixed Qt (Qt): 6.8.4, 6.9.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
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
qtQt5.15.0 – 6.8.3; 6.9.0 to before 6.9.26.8.4, 6.9.2Patch availableCNA
  • Qt Vendorqt Affected 5.15.0 – 6.8.3; 6.9.0 to before 6.9.2 Fixed in 6.8.4, 6.9.2 Patch available CNA

Remediation

  • Fix · CNA Qt (Qt) Fixed in 6.8.4, 6.9.2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-6338
  2. 2026-10-03 Alias added: GHSA-m4hj-jpxf-jhjp

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