Critical severity · published Aug 1, 2024
CVE-2024-39777
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…
9.6
CVSS
0.4%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 30% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
9.5.0 before 9.5.7; 9.7.0 before 9.7.6; 9.8.0 before 9.8.2; 9.9.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2024-39777
CVE.org
https://www.cve.org/CVERecord?id=CVE-2024-39777
Vendor Advisory
https://mattermost.com/security-updates
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