CVE-2026-8683 (GCVE-0-2026-8683)

Vulnerability from cvelistv5 – Published: 2026-06-15 14:06 – Updated: 2026-06-15 16:06
VLAI?
Title
Overly long URLs crash the Mattermost Desktop App
Summary
Mattermost Desktop App versions <=6.1 5.5.13.0 fail to account for attempting to open extremely long URLs in the Mattermost Desktop App which allows a malicious server owner to crash the application via including a script to call window.open on a very large URL. Mattermost Advisory ID: MMSA-2026-00652
Severity ?
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 0 , ≤ 5.5.13 (semver)
Unaffected: 6.2.0
Unaffected: 5.13.6.0
Create a notification for this product.
Credits
game0v3r
Show details on NVD website
To clipboard 

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  • 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.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.