CVE-2026-1046 (GCVE-0-2026-1046)

Vulnerability from cvelistv5 – Published: 2026-02-16 12:10 – Updated: 2026-02-17 17:05
VLAI?
Title
Arbitrary application execution via unvalidated server-controlled URLs in Help menu
Summary
Mattermost Desktop App versions <=6.0 6.2.0 5.2.13.0 fail to validate help links which allows a malicious Mattermost server to execute arbitrary executables on a user’s system via the user clicking on certain items in the Help menu Mattermost Advisory ID: MMSA-2026-00577
Severity ?
7.6 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:N/A:L
CWE
  • CWE-939 - Improper Authorization in Handler for Custom URL Scheme
Assigner
References
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 0 , ≤ 6.2.0 (semver)
Affected: 0 , ≤ 5.2.13 (semver)
Unaffected: 6.1.0
Unaffected: 6.0.3.0
Unaffected: 5.13.3.0
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Credits
hackerman70000
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.
  • 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.