CVE-2026-28735
Published: May 22, 2026
Modified: May 22, 2026
CVSS v3.1
5.4
Description
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate the OAuth token scope on the callback which allows an authenticated Mattermost user to gain access to private repositories via modifying the scope parameter in the GitHub authorization URL.. Mattermost Advisory ID: MMSA-2026-00628
| Vendor | Product | Versions |
|---|---|---|
Mattermost | Mattermost | affected 11.6.0 - <= 11.6.0affected 11.5.0 - <= 11.5.3affected 11.4.0 - <= 11.4.4affected 10.11.0 - <= 10.11.14unaffected 11.7.0+4 more versions |
Weaknesses (CWE)
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
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