CVE-2026-14298 json
Boards archive import endpoint allows resource exhaustion via zip bomb and file size limit bypass in Mattermost
published 2mo ago modified last mo. also EUVD-2026-57742
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 36%
- public exploits
- 0
- none known
Summary
Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to limit decompressed content size and enforce the configured maximum file size in the Boards archive import handler, which allows an authenticated user to cause memory exhaustion or unbounded disk consumption via a crafted .boardarchive file uploaded to the import endpoint.. Mattermost Advisory ID: MMSA-2026-00713
Patch / fix
- Mattermost Mattermost 10.11.23, 11.7.8, 11.8.5, 11.9.1, 11.10.0
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.42% chance of exploitation in the next 30 days, higher than 36% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Affected products
- Mattermost Mattermost
Classification
- Weakness
-
- CWE-409 Improper Handling of Highly Compressed Data (Data Amplification)
References
-
mattermost.com
/security-updates
vendor-advisory
Sources
- CVE List CVE-2026-14298
- NVD CVE-2026-14298
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