CVE-2026-4643 (GCVE-0-2026-4643)

Vulnerability from cvelistv5 – Published: 2026-05-18 08:43 – Updated: 2026-05-18 14:36
VLAI
Title
Calling window.close() from server-side content causes crash in the Mattermost Desktop App
Summary
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
Severity
3.5 (Low)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L
CWE
  • CWE-754 - Improper Check for Unusual or Exceptional Conditions
Assigner
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 0 , ≤ 6.0.1 (semver)
Affected: 0 , ≤ 5.4.13 (semver)
Unaffected: 6.2.0
Unaffected: 6.1.1.0
Unaffected: 5.13.5.0
Create a notification for this product.
Credits
Devin Binnie
Show details on NVD website
To clipboard 

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Taxonomy of the tags.




Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.