Vulnerabilities in Mattermost
512 resultsCVE-2026-2456MEDIUMDenial of Service via Unbounded Memory Allocation in Integration ActionsEPSS 0.2%CVE-2026-2455MEDIUMSSRF bypass via IPv4-mapped IPv6 literalsEPSS 0.2%CVE-2025-9084LOWOpen redirect in OAuth loginEPSS 0.2%CVE-2026-4643LOWCalling window.close() from server-side content causes crash in the Mattermost Desktop AppEPSS 0.2%CVE-2026-2461MEDIUMMissing authorization check allows unauthorized modification of other users' comments on a boardEPSS 0.2%CVE-2026-26230LOWTeam Admin Privilege Escalation to Demote Members to GuestEPSS 0.2%CVE-2026-26304MEDIUMPermission Bypass in Playbook Run CreationEPSS 0.2%CVE-2026-27769LOWConnected Workspaces: Malicious remote server can manipulate arbitrary user's statusEPSS 0.2%CVE-2026-4053LOWpost edit time limit is not enforced on some post update operationsEPSS 0.2%CVE-2026-6343MEDIUMMattermost Playbooks Plugin fails to enforce view permissions in list endpoints, allowing unauthorized access to public playbooksEPSS 0.2%CVE-2026-12284LOWMattermost Desktop App Missing IPC Sender Validation in Calls Leave HandlerEPSS 0.2%CVE-2024-46872MEDIUMClient-Side Path Traversal Leading to CSRF in PlaybooksEPSS 0.2%CVE-2026-18256MEDIUMPrivate team metadata disclosure via the team search APIEPSS 0.2%CVE-2026-1628MEDIUMMattermost allows external websites to open within the app, exposing preload functionality to non-trusted sites.EPSS 0.2%CVE-2026-18223MEDIUMMattermost invitation tokens not bound to invited email address allowing unauthorized team and private channel accessEPSS 0.2%CVE-2026-75025MEDIUMMattermost Desktop local network access from server-rendered contentEPSS 0.2%CVE-2026-22545LOWPassword Change Bypass via Auth Switch EndpointEPSS 0.2%CVE-2025-59480MEDIUMInadequate validation of SSO redirect credentials permits credential theftEPSS 0.2%CVE-2025-9078MEDIUMWeak cache keys lead to post IDOR and link preview poisoningEPSS 0.2%CVE-2026-6342MEDIUMGroup prefix matching bypass for subscriptionsEPSS 0.2%