5.3

CVE-2026-6046

Plugin bot username conflict allows user account to be used as bot identity in Mattermost Server

Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 fail to validate that a username returned during bot registration belongs to a bot account, which allows an unprivileged attacker to intercept private messages sent by plugins via direct message channels by pre-registering a user account with a predictable plugin bot username.. Mattermost Advisory ID: MMSA-2026-00649
Daten sind bereitgestellt durch das CVE Programm von einer CVE Numbering Authority (CNA) (Unstrukturiert).
HerstellerMattermost
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Produkt Mattermost
Default Statusunaffected
Version <= 11.6.1
Version 11.6.0
Status affected
Version <= 11.5.4
Version 11.5.0
Status affected
Version <= 10.11.15
Version 10.11.0
Status affected
Version <= 10.11.16
Version 10.11.0
Status affected
Version 11.7.0
Status unaffected
Version 11.6.2
Status unaffected
Version 11.5.5
Status unaffected
Version 10.11.16
Status unaffected
Version 10.11.17
Status unaffected
VulnDex Vulnerability Enrichment
Diese Information steht angemeldeten Benutzern zur Verfügung. Login Login
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.19% 0.087
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
responsibledisclosure@mattermost.com 5.3 1.6 3.6
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

https://mattermost.com/security-updates