CVE-2025-27933mediumCWE-863

CVE-2025-27933: medium-severity vulnerability in Mattermost

Unauthorized Private-to-Public Channel Conversion

Published

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 5.4epss 0.2%
Mattermost versions 10.4.x <= 10.4.2, 10.3.x <= 10.3.3, 9.11.x <= 9.11.8 fail to fail to enforce channel conversion restrictions, which allows members with permission to convert public channels to private ones to also convert private ones to public
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Affected products
Mattermost · Mattermost
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In the same product, most dangerous first.

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