Qt up to 6.8.8/6.11.2 VNC Server improper authentication

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-$5k0.00+

Summaryinfo

A vulnerability categorized as critical has been discovered in Qt up to 6.8.8/6.11.2. Impacted is an unknown function of the component VNC Server. The manipulation results in improper authentication. This vulnerability is identified as CVE-2026-79680. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Qt up to 6.8.8/6.11.2. It has been classified as critical. Affected is an unknown functionality of the component VNC Server. The manipulation with an unknown input leads to a improper authentication vulnerability. CWE is classifying the issue as CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Authentication bypass vulnerability in the password authentication mechanism of the Qt VNC Server module. An attacker using a specially modified VNC client that violates the RFB protocol can bypass Qt VNC Server's password authentication and gain unauthorized remote access to the shared application, compromising the confidentiality and integrity of the session.

The advisory is available at wiki.qt.io. This vulnerability is traded as CVE-2026-79680 since 08/25/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available.

Upgrading to version 6.8.9 or 6.11.3 eliminates this vulnerability.

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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: Improper authentication
CWE: CWE-287
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: Qt 6.8.9/6.11.3

Timelineinfo

08/25/2026 CVE reserved
09/24/2026 +30 days Advisory disclosed
09/24/2026 +0 days VulDB entry created
09/24/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: wiki.qt.io
Status: Confirmed

CVE: CVE-2026-79680 (🔒)
GCVE (CVE): GCVE-0-2026-79680
GCVE (VulDB): GCVE-100-409326

Entryinfo

Created: 09/24/2026 13:20
Changes: 09/24/2026 13:20 (68)
Complete: 🔍
Cache ID: 216::103

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