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Fencer Vulns
high 8.7

CVE-2026-16762 json

Denial-of-service vulnerability in the Qt Core QXmlStream parser (QXmlStreamReader) impacts Qt

published 2026-10-23 17 d ago modified 2026-10-23 16 d ago also EUVD-2026-108655

cvss
8.7
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 44%
public exploits
0
none known

Summary

An attacker able to supply a crafted XML document to an application using QXmlStreamReader can cause disproportionate CPU consumption during parsing, making the application unresponsive (denial of service). Exploitation requires only that the application parse attacker-influenced XML; no authentication, privileges, or user interaction beyond ingesting the input are needed. There is no loss of confidentiality or integrity — no data disclosure, data modification, or code execution — and the impact is contained to the affected process.

Patch / fix

  • qt qt 6.8.9, 6.11.2
  • qt6-base Debian 14 6.11.2+dfsg-5

debian advisories DEBIAN-CVE-2026-16762

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-16762 updated cvss 7.5

qt: qt: Denial of Service via crafted XML parsing in QXmlStreamReader

  • Red Hat Enterprise Linux 6 qt, qt-x11, qt-odbc, qt-demos, qt-mysql, qt3-ODBC, +10 more Red Hat Enterprise Linux 7 qt, qt-x11, qt-odbc, qt-qvfb, qt-demos, qt-mysql, +12 more Red Hat Enterprise Linux 8 qt5, qt5-rpm-macros, qt5-srpm-macros Red Hat Enterprise Linux 9 qt5, qt5-rpm-macros, qt5-srpm-macros Red Hat Enterprise Linux 10 qt6 6.10.1-1.el10 Red Hat Hardened Images qt6 6.10.1-1.el10
    affected: no fix available
  • Red Hat Hardened Images qt5
    not affected: component not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
17 d ago

Exploit prediction

0.52% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 4.0 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/S:P/AU:Y/R:A/RE:L
CNA 4.0 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:P/AU:Y/R:A/V:X/RE:L/U:X

Affected products

  • qt qt

Classification

Weakness
  • CWE-407 Inefficient Algorithmic Complexity

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.