CVE-2018-21251

9.8 criticalEPSS 1.2%

Critical (9.8) in mattermost mattermost server. EPSS 1.2% chance of exploitation in the next 30 days.

An issue was discovered in Mattermost Server before 5.2 and 5.1.1. Authorization could be bypassed if the channel name were not the same in the params and the body.

Severity

CVSS 3.1

9.8 critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS: 1.2% chance of exploitation in the next 30 days; higher than 68% of CVEs (scores of 2026-10-31)
CWE: CWE-862
Published: 2020-06-19
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

mattermost:mattermost_server

References

https://mattermost.com/security-updates/
https://mattermost.com/security-updates/

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