CVE-2026-28735
Analyzed Analyzed - Analysis Complete
BaseFortify

Publication date: 2026-05-22

Last updated on: 2026-05-22

Assigner: Mattermost, Inc.

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
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Meta Information
Published
2026-05-22
Last Modified
2026-05-22
Generated
2026-05-26
EPSS Evaluated
N/A
NVD
EUVD
Affected Vendors & Products
Showing 4 associated CPEs
Vendor Product Version / Range
mattermost mattermost_server From 10.11.0 (inc) to 10.11.15 (exc)
mattermost mattermost_server From 11.4.0 (inc) to 11.4.5 (exc)
mattermost mattermost_server From 11.5.0 (inc) to 11.5.4 (exc)
mattermost mattermost_server From 11.6.0 (inc) to 11.6.1 (exc)
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-863 The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
Attack-Flow Graph
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