Medium severity · published Aug 1, 2024
CVE-2024-29977
Malicious remote can create arbitrary reactions on arbitrary posts
4.3
CVSS
0.3%
EPSS
No
On KEV
Description
Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6 fail to properly validate synced reactions, when shared channels are enabled, which allows a malicious remote to create arbitrary reactions on arbitrary posts
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
9.9.0; 9.5.0 through 9.5.6 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2024-29977
CVE.org
https://www.cve.org/CVERecord?id=CVE-2024-29977
Vendor Advisory
https://mattermost.com/security-updates
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