CVE-2026-7387
Auth bypass allows escalation to team/channel admin via crafted API requests
Is CVE-2026-7387 being exploited?
Not confirmed. CVE-2026-7387 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.31% probability of exploitation in the next 30 days.
How severe is CVE-2026-7387?
CVE-2026-7387 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-7387?
Yes. A fix has been recorded for CVE-2026-7387. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-7387 affect?
CVE-2026-7387 affects Mattermost 11.6.x <= 11.6.1, Mattermost 11.5.x <= 11.5.4, Mattermost 10.11.x <= 10.11.15, Mattermost 10.11.x <= 10.11.16. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-7387?
Apply latest Mattermost patch; audit group-link permissions
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authorization bypass lets a group-link user elevate themselves and others to admin by abusing group-link endpoints.
Patch when possible
- affected>= 11.6.0 and <= 11.6.1
- affected>= 11.5.0 and <= 11.5.4
- affected>= 10.11.0 and <= 10.11.15
- affected>= 10.11.0 and <= 10.11.16
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.