Malicious remote can create arbitrary reactions on arbitrary posts
8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 2.7epss 0.3%
exploitation probability
0.3%top 80% of all CVEs
observed exploitation
nono source reports it
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:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:N
Affected products
Mattermost · MattermostReferences
https://mattermost.com/security-updates