9.2

CVE-2025-6338: qt Incomplete Cleanup

CVSS: 9.2v4.0CriticalDeferred
Published 16-10-2025Last modified 29-07-2026
Open JSON

Vulnerability summary

CVE-2025-6338 is a critical (CVSS 9.2) Incomplete Cleanup vulnerability in qt. EPSS estimates a 0.43% chance of exploitation in the next 30 days, higher than 35.5% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.2/10
010
Critical · v4.0 (CVE.org)
EPSS score
0.43%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 16-10-2025
    PublishedVulnerability first disclosed.
  2. 29-07-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.43%

Chance of exploitation in the next 30 days

Percentile

36%

Versus all other CVEs

30-day change

0.00 pp

From 0.42% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.43%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Qt1 product
  • qt≥ 5.15.0, ≤ 6.8.3 | ≥ 6.9.0, < 6.9.2

1 vendor · 1 product

References

1 links