How severe is CVE-2021-37864?

CVE-2021-37864 has a CVSS 3.x base score of 2.6, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-37864 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-37864?

CVE-2021-37864 affects Mattermost. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-37864?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-37864 published?

CVE-2021-37864 was published on 2022-01-18 and last updated on 2026-06-17.

CVE-2021-37864

CVE-2021-37864 is a low-severity vulnerability in Mattermost with a CVSS 3.x base score of 2.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-863.

Key facts

Severity: Low (CVSS 3.x base score 2.6)
CVSS v2: 4.0
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Mattermost
Published: 2022-01-18
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2021-37864?: CVE-2021-37864 has a CVSS 3.x base score of 2.6, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-37864 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-37864?: CVE-2021-37864 affects Mattermost. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-37864?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-37864 published?: CVE-2021-37864 was published on 2022-01-18 and last updated on 2026-06-17.

References

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

Affected products (1)

cpe:2.3:a:mattermost:mattermost:*:*:*:*:*:*:*:*

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