Mattermost versions 10.1.x <= 10.1.2, 10.0.x <= 10.0.2, 9.11.x <= 9.11.4, 9.5.x <= 9.5.12 fail to limit the file size for slack import file uploads which allows a user to cause a DoS via zip bomb by importing data in a team they are a team admin.
https://mattermost.com/security-updates
Source: Mitre, NVD
Published: 2024-12-16
Updated: 2025-09-30
Base Score: 6.1
Vector: CVSS2#AV:N/AC:L/Au:M/C:N/I:N/A:C
Severity: Medium
Base Score: 4.9
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.00061