What is CVE-2021-37864?

CVE-2021-37864 is a low-severity vulnerability in Mattermost, classified under Improper Access Control. CVSS score: 2.6/10. Published 2022-01-18.

How severe is CVE-2021-37864?

Low severity. CVSS v3 base score is 2.6 out of 10.

Auth bypass in Mattermost

CVE-2021-37864

Mattermost 6.1 and earlier fails to sufficiently validate permissions while viewing archived channels, which allows authenticated users to view contents of archived channels even when this is denied by system administrators by directly accessing the APIs.

Published 2022-01-18 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 2.6 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.006 (45.8th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 45.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Mattermost — versions unspecified

Weakness classification (CWE)

References

mattermost.com/security-updates/ (Vendor Advisory)

Frequently asked questions

What is CVE-2021-37864?: CVE-2021-37864 is a low-severity vulnerability in Mattermost, classified under Improper Access Control. CVSS score: 2.6/10. Published 2022-01-18.
How severe is CVE-2021-37864?: Low severity. CVSS v3 base score is 2.6 out of 10.