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
Metrics
Affected Vendors & Products
References
| Link | Providers |
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| https://mattermost.com/security-updates |
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History
Fri, 22 May 2026 17:45:00 +0000
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Fri, 22 May 2026 17:30:00 +0000
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ssvc
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Fri, 22 May 2026 16:30:00 +0000
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| 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 | |
| Title | GitHub OAuth Scope Validation | |
| Weaknesses | CWE-863 | |
| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: Mattermost
Published:
Updated: 2026-05-22T16:56:09.671Z
Reserved: 2026-03-10T13:45:39.998Z
Link: CVE-2026-28735
Updated: 2026-05-22T16:55:49.531Z
No data.
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OpenCVE Enrichment
Updated: 2026-05-22T17:30:06Z