CVE-2021-37865 json
Server-side Denial of Service while processing a specifically crafted GIF file
published 2022-01-18 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-24343
- cvss
- 4.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 59%
- public exploits
- 0
- none known
Summary
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.
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 23 mo ago
Exploit prediction
0.90% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L |
| NVD | 3.1 | 5.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 3.5 | AV:N/AC:M/Au:S/C:N/I:N/A:P |
Affected products
- Mattermost Mattermost
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
References
-
mattermost.com
/security-updates/
vendor-advisory
-
hackerone.com
/reports/1428260
permissions-required
Sources
- CVE List CVE-2021-37865
- NVD CVE-2021-37865
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