CVE-2021-37863

lowpriority · track · 23EPSS 0.009 · 58 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.86% (58th) EPSS

CVSS 3.5 · low

Is it mine?

3 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

Mattermost 6.0 and earlier fails to sufficiently validate parameters during post creation, which allows authenticated attackers to cause a client-side crash of the web application via a maliciously crafted post.

cvss

Technical severity, 0–10. One row per scoring source.

5.7

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.5–5.7

v2.03.5lowAV:N/AC:M/Au:S/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 6.8 · impact 2.9

v3.15.7mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.1 · impact 3.6

v3.13.5lowCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:Lsecondary · ENISA EU

v3.13.5lowCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:Lsecondary · responsibledisclosure@mattermost.comexploitability 2.1 · impact 1.4

v3.15.2mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimary

affected products (3)

Products and version ranges known to be affected.

Mattermost Mattermost≤ unspecified ≤6.0enisa_euvdEU
mattermost mattermost server≤ 6.0nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
Bitnami mattermost< 6.0.1osvUSpkg:bitnami/mattermost

advisories (1)

Vendor and ecosystem advisories describing this.

BIT-mattermost-2021-378632024-03-06vendor · osvUS
Mattermost 6.0 and earlier fails to sufficiently validate parameters during post creation, which allows authenticated attackers to cause a client-side crash of the web application via a maliciously crafted post.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd osv NVD CVE.org MITRE

published 2021-12-17modified 2026-06-17

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references (8)

External citations — patches, advisories, analysis.

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