cbcvebase.
CVE-2025-9076
published 2025-09-15

CVE-2025-9076: Mattermost versions 10.10.x <= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or…

PriorityP339medium6.5CVSS 3.1
AVNACLPRLUINSUCHINAN
EPSS
0.24%
15.5th percentile
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.

Affected

8 ranges
VendorProductVersion rangeFixed in
github.commattermost_mattermost-server>= 10.10.0 < 10.10.210.10.2
github.commattermost_mattermost-server>= 10.10.0+incompatible < 10.10.2+incompatible10.10.2+incompatible
github.commattermost_mattermost_server_v8>= 0 < 8.0.0-20250729073403-517ae758cd028.0.0-20250729073403-517ae758cd02
mattermostmattermost10.10.0 – 10.10.1
mattermostmattermost_server>= 10.10.0 < 10.10.210.10.2
msrccbl_mariner_1.0_arm
msrccbl_mariner_1.0_x64
msrccm1_binutils_2.32-4_on_cbl_mariner_1.0

CVSS provenance

nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
vendor_msrc5.5MEDIUM
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