CVE-2026-6210 | Type confusion and heap-buffer-overflow in Qt SVG marker handling causing application crash

A type confusion vulnerability in Qt SVG allows an attacker to cause an application crash via a crafted SVG image. When processing SVG marker references, the renderer retrieves a node by its id attribute and casts it to QSvgMarker* without verifying the node type. A non-marker element (such as a <line> element) that references itself as a marker triggers an out-of-bounds heap read due to the object size difference between QSvgLine and QSvgMarker, followed by an endless recursion that bypasses the marker recursion guard through incorrect virtual dispatch. The result is an application crash (denial of service). This issue affects Qt SVG:  from 6.7.0 before 6.8.8, from 6.9.0 before 6.11.1.

Published: 2026-05-06 Last update: 2026-05-07 Assigner: a59d8014-47c4-4630-ab43-e1b13cbe58e3 Source: a59d8014-47c4-4630-ab43-e1b13cbe58e3
NVD Status：Awaiting Analysis，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-6210 is rated Moderate Risk (40.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.06%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-6210

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-12 0.04% 0.06% +0.01%
2 2026-05-07 — 0.04% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-6210

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.7 4.0 HIGH
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:X/AU:X/R:X/V:X/RE:X/U:X Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N)
No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:H)
High availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:X)
Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked).
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:X)
Not evaluated.
Recovery (supplemental) (R:X)
Not evaluated.
Value density (supplemental) (V:X)
Not evaluated.
Vulnerability response effort (supplemental) (RE:X)
Not evaluated.
Provider urgency (supplemental) (U:X)
Not evaluated.
 — — a59d8014-47c4-4630-ab43-e1b13cbe58e3

Weakness enumeration for CVE-2026-6210

GitHub Security Advisory for CVE-2026-6210

GHSA-mh4x-qpf6-hr3q · Severity: high — A type confusion vulnerability in Qt SVG allows an attacker to cause an application crash via a...

OS Trackers for CVE-2026-6210

vendor priority summary link
debian not yet assigned CVE-2026-6210 not yet assigned priority: Debian including 2 source packages (qt6-svg, qtsvg-opensource-src), 9 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 7, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-6210
suse medium — https://www.suse.com/security/cve/CVE-2026-6210/
ubuntu medium CVE-2026-6210 medium priority: Ubuntu including 2 source packages (qt6-svg, qtsvg-opensource-src), 13 status rows across 8 suites (bionic, focal, jammy, noble, questing, resolute, upstream, xenial): needs-triage 12, released 1. https://ubuntu.com/security/CVE-2026-6210

Affected software / configurations for CVE-2026-6210

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-6210

cvelogic Threat Intelligence