CVE-2025-9076 (GCVE-0-2025-9076)

Vulnerability from cvelistv5 – Published: 2025-09-15 10:06 – Updated: 2025-09-15 14:05
VLAI?
Summary
Mattermost versions 10.10.x <= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user objects. This vulnerability affects Mattermost Server instances with shared channels enabled.
Severity ?
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
CWE
Assigner
References
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 10.10.0 , ≤ 10.10.1 (semver)
Unaffected: 10.11.0
Unaffected: 10.10.2
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Credits
daw10
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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.
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