CVE-2021-37865
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…
Does this matter?
Lower severity and a low EPSS score (0.90%). Track it; it rarely justifies an emergency change on its own.
Description
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 3.1
- 5.7 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
- EPSS
- 0.90% probability · 59th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-400
- Affected
- mattermost/mattermost
- Source
- responsibledisclosure@mattermost.com
EPSS 0.9% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://hackerone.com/reports/1428260Permissions Required
- https://mattermost.com/security-updates/Vendor Advisory
- https://hackerone.com/reports/1428260Permissions Required
- https://mattermost.com/security-updates/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.