CVE-2026-1628 (GCVE-0-2026-1628)

Vulnerability from cvelistv5 – Published: 2026-03-02 13:24 – Updated: 2026-03-02 14:58
VLAI?
Title
Mattermost allows external websites to open within the app, exposing preload functionality to non-trusted sites.
Summary
Mattermost Desktop App versions <=5.13.3 fail to attach listeners restricting navigation to external sites within the Mattermost app which allows a malicious server to expose preload script functionality to untrusted servers via having a user open an external link in their Mattermost server. Mattermost Advisory ID: MMSA-2026-00596
Severity ?
4.6 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
CWE
  • CWE-829 - Inclusion of Functionality from Untrusted Control Sphere
Assigner
References
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 0 , ≤ 5.13.3 (semver)
Unaffected: 5.13.4.0
Create a notification for this product.
Credits
N/A
Show details on NVD website
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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.
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  • 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.