CVE-2026-95509 - Vulnerability Details - OpenCVE

Strings optimized for Latin-1 displaying Latin-1 characters cause incorrect String.arg() formatting by an incorrect buffer size calculation, causing out-of-bounds reading.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact Low

Vulnerable System Integrity Impact Low

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

qt

Qt for MCUs

unaffected

Version	Status	Constraints
`2.6.0`	affected	< 2.11.3
`2.12.0`	affected	< 2.12.3

No data.

No data.

No data.

Project Subscriptions

Vendors	Products
Qt Subscribe	Qt For Mcus Subscribe

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://wiki.qt.io/List_of_known_vulnerabilities_in_Qt_products#CVE-2026-95509:

History

Tue, 29 Sep 2026 13:15:00 +0000

Type	Values Removed	Values Added
Description		Strings optimized for Latin-1 displaying Latin-1 characters cause incorrect String.arg() formatting by an incorrect buffer size calculation, causing out-of-bounds reading.
Title		Out-of-bounds read vulnerability in string formatting impacts Qt for MCUs
First Time appeared		Qt Qt qt For Mcus
Weaknesses		CWE-125 CWE-131
CPEs		cpe:2.3:a:qt:qt_for_mcus::::::::
Vendors & Products		Qt Qt qt For Mcus
References		https://wiki.qt.io/List_of_known_vulnerabilities_in_Qt_products#CVE-2026-95509:
Metrics		cvssV4_0 `{'score': 8.8, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: Qt

Published: 2026-09-29T10:40:12.578Z

Updated: 2026-09-29T10:40:12.578Z

Reserved: 2026-09-22T07:25:57.557Z

Link: CVE-2026-95509

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-09-29T11:16:43.947

Modified: 2026-09-29T11:16:43.947

Link: CVE-2026-95509

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

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