CVE-2026-3108: high-severity vulnerability in Mattermost
Terminal Escape Injection in mmctl Report Posts Command
Published · Updated
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8epss 0.3%
exploitation probability
0.3%top 74% of all CVEs
observed exploitation
nono source reports it
Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to sanitize user-controlled post content in the mmctl commands terminal output which allows attackers to manipulate administrator terminals via crafted messages containing ANSI and OSC escape sequences that enable screen manipulation, fake prompts, and clipboard hijacking.. Mattermost Advisory ID: MMSA-2026-00599
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H
Affected products
Mattermost · MattermostRelated CVEs — Mattermost
In the same product, most dangerous first.
CVE-2025-25279CRITICALArbitrary file read in Mattermost Boards via import & export board archiveEPSS 24.2%CVE-2021-37859HIGHReflected XSS in OAuth FlowEPSS 3.3%CVE-2022-3257LOWServer-side Denial of Service while processing a specifically crafted GIF fileEPSS 1.3%CVE-2022-4044MEDIUMAuthenticated user could send multiple requests containing a large Auto Responder Message payload and can crash a Mattermost serverEPSS 1.1%CVE-2022-3147LOWServer-side Denial of Service while processing a specifically crafted JPEG fileEPSS 1.0%CVE-2022-1982MEDIUMA crafted SVG attachment can crash a Mattermost serverEPSS 0.9%
References
https://mattermost.com/security-updates