Mattermost Desktop App up to 5.4.13/6.0.1/6.1.x window.close unusual condition

CVSS Meta Temp Score
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CTI Interest Score
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3.8$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Mattermost Desktop App up to 5.4.13/6.0.1/6.1.x. Affected by this issue is the function window.close. The manipulation results in unusual condition. This vulnerability is cataloged as CVE-2026-4643. The attack may be launched remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Mattermost Desktop App up to 5.4.13/6.0.1/6.1.x. Affected is the function window.close. The manipulation with an unknown input leads to a unusual condition vulnerability. CWE is classifying the issue as CWE-754. The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product. This is going to have an impact on availability. CVE summarizes:

Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent server-rendered content from closing an underlying application view in the Mattermost Desktop App which allows a malicious server or plugin to crash the desktop client via invoking {{window.close()}} in the renderer context, leading to a denial of service condition at the client level. Mattermost Advisory ID: MMSA-2026-00633

The weakness was shared by Devin Binnie. The advisory is shared for download at mattermost.com. This vulnerability is traded as CVE-2026-4643 since 03/23/2026. 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 5.13.5.0, 6.1.1.0 or 6.2.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at EUVD (EUVD-2026-30758) and CERT Bund (WID-SEC-2026-1565). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Mattermost Mattermost

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.9
VulDB Meta Temp Score: 3.8

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 3.5
CNA Vector (Mattermost): 🔒

CVSSv2info

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

Exploitinginfo

Class: Unusual condition
CWE: CWE-754
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

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: Desktop App 5.13.5.0/6.1.1.0/6.2.0

Timelineinfo

03/23/2026 CVE reserved
05/18/2026 +55 days Advisory disclosed
05/18/2026 +0 days VulDB entry created
05/19/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: Devin Binnie
Status: Confirmed

CVE: CVE-2026-4643 (🔒)
GCVE (CVE): GCVE-0-2026-4643
GCVE (VulDB): GCVE-100-364464
EUVD: 🔒
CERT Bund: WID-SEC-2026-1565 - Mattermost Desktop: Mehrere Schwachstellen erm&ouml;glichen nicht spezifizierten Angriff

Entryinfo

Created: 05/18/2026 12:28
Updated: 05/19/2026 10:05
Changes: 05/18/2026 12:28 (65), 05/18/2026 15:34 (1), 05/19/2026 10:05 (7)
Complete: 🔍
Cache ID: 216::103

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

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