CVE-2024-39777highCWE-284

CVE-2024-39777: high-severity vulnerability in Mattermost

Malicious remote can invite itself to an arbitrary local channel

Published

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21Vexday Risk Score

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

ssvc Trackcvss 8.7epss 0.4%
Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5 and 9.8.x <= 9.8.1 fail to disallow unsolicited invites to expose access to local channels, when shared channels are enabled, which allows a malicious remote to send an invite with the ID of an existing local channel, and that local channel will then become shared without the consent of the local admin.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N
Affected products
Mattermost · Mattermost
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