Qt for MCUs up to 2.11.2/2.12.2 String.arg out-of-bounds

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Qt for MCUs up to 2.11.2/2.12.2. This impacts the function String.arg. The manipulation results in out-of-bounds. This vulnerability was named CVE-2026-95509. The attack may be performed from remote. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Qt for MCUs up to 2.11.2/2.12.2. It has been classified as critical. Affected is the function String.arg. The manipulation with an unknown input leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at wiki.qt.io. This vulnerability is traded as CVE-2026-95509 since 09/22/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. There are known technical details, but no exploit is available.

Upgrading to version 2.11.3 or 2.12.3 eliminates this vulnerability.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: for MCUs 2.11.3/2.12.3

Timelineinfo

09/22/2026 CVE reserved
09/29/2026 +7 days Advisory disclosed
09/29/2026 +0 days VulDB entry created
09/29/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: wiki.qt.io
Status: Confirmed

CVE: CVE-2026-95509 (🔒)
GCVE (CVE): GCVE-0-2026-95509
GCVE (VulDB): GCVE-100-411288

Entryinfo

Created: 09/29/2026 13:02
Changes: 09/29/2026 13:02 (66)
Complete: 🔍
Cache ID: 216::103

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