CVE-2021-37865

lowpriority · track · 23EPSS 0.009 · 59 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.90% (59th) EPSS

CVSS 3.5 · low

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

Mattermost 6.2 and earlier fails to sufficiently process a specifically crafted GIF file when it is uploaded while drafting a post, which allows authenticated users to cause resource exhaustion while processing the file, resulting in server-side Denial of Service.

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

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Lsecondary · ENISA EU

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Lsecondary · responsibledisclosure@mattermost.comexploitability 2.8 · 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)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USprimary

affected products (2)

Products and version ranges known to be affected.

Mattermost Mattermost≤ unspecified ≤6.2enisa_euvdEU
mattermost mattermost≤ 6.2.0nvdUScpe:2.3:a:mattermost:mattermost:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2022-01-18modified 2026-06-17

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+9607 more

references (7)

External citations — patches, advisories, analysis.

scry

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