CVE-2026-4915
Published: May 25, 2026
Modified: May 26, 2026
CVSS v3.1
6.5
Description
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to filter nil elements from outgoing webhook attachment payloads before processing, which allows an authenticated user to cause a denial of service (server process termination) via a crafted webhook callback response containing a null attachment entry.. Mattermost Advisory ID: MMSA-2026-00641
| Vendor | Product | Versions |
|---|---|---|
Mattermost | Mattermost | affected 11.6.0 - <= 11.6.0affected 11.5.0 - <= 11.5.3affected 11.4.0 - <= 11.4.4affected 10.11.0 - <= 10.11.14unaffected 11.7.0+4 more versions |
Weaknesses (CWE)
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
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