CVE-2026-15814
Uploading a crafted image causes excessive memory allocation in the Mattermost Server
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th
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 the amount of memory allocated when decoding uploaded image files which allows an authenticated user to cause excessive server memory consumption and potential denial of service via uploading a specially crafted image as a profile picture, channel file attachment, team icon, or custom brand image. Mattermost Advisory ID: MMSA-2026-00719
| CWE | CWE-409 |
| Vendor | mattermost |
| Product | mattermost |
| Published | Sep 14, 2026 |
| Last Updated | Sep 14, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
Mattermost / Mattermost
11.9.0 ≤ 11.9.0 11.8.0 ≤ 11.8.4 11.7.0 ≤ 11.7.7 10.11.0 ≤ 10.11.22
Credits
alimursaliyev