Qt up to 4.4.x/6.8.8/6.11.2 Qt 5 Compatibility APIs module out-of-bounds write

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.0$0-$5k1.59

Summaryinfo

A vulnerability was found in Qt up to 4.4.x/6.8.8/6.11.2. It has been declared as critical. This vulnerability affects unknown code of the component Qt 5 Compatibility APIs module. The manipulation results in out-of-bounds write. This vulnerability was named CVE-2026-107590. The attack may be performed from remote. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Qt up to 4.4.x/6.8.8/6.11.2. Affected is some unknown processing of the component Qt 5 Compatibility APIs module. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. CWE is classifying the issue as CWE-787. The product writes 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:

An out-of-bounds write vulnerability in the Qt QTextCodec iconv-based encoding of the Qt 5 Compatibility APIs module (Qt Core in Qt 5 and earlier) impacts Qt. Under certain conditions, encoding text with QTextCodec may write outside an internal buffer. This can cause the application to crash and may affect data integrity.

The advisory is shared for download at wiki.qt.io. This vulnerability is traded as CVE-2026-107590 since 10/08/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available.

Upgrading to version 4.5.0 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

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: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
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 write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
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: Qt 4.5.0

Timelineinfo

10/08/2026 CVE reserved
10/27/2026 +19 days Advisory disclosed
10/27/2026 +0 days VulDB entry created
10/27/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: wiki.qt.io
Status: Confirmed

CVE: CVE-2026-107590 (🔒)
GCVE (CVE): GCVE-0-2026-107590
GCVE (VulDB): GCVE-100-427188

Entryinfo

Created: 10/27/2026 13:47
Changes: 10/27/2026 13:47 (69)
Complete: 🔍
Cache ID: 216::103

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