Auth bypass in Mythicalltd Featherpanel
CVE-2026-84715
FeatherPanel versions before 1.3.7.10 fail to validate permissions in the SubuserController updateSubuser handler, allowing authenticated subusers to modify their own permission records. A subuser with minimal permissions can send a crafted request to grant themselves full server control, enabling unauthorized access to sensitive data, backups, and server configuration.
Vulnerability class: Broken Access Control
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
Weakness classification (CWE)
References
- disclosure@vulncheck.com (patch)
- disclosure@vulncheck.com (release-notes)
- disclosure@vulncheck.com (technical-description)
- disclosure@vulncheck.com (technical-description)
- disclosure@vulncheck.com (product)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-84715?
- CVE-2026-84715 is a high-severity vulnerability in Mythicalltd Featherpanel, classified under Missing Authorization. CVSS score: 8.8/10. Published 2026-09-02.
- How severe is CVE-2026-84715?
- High severity. CVSS v3 base score is 8.8 out of 10.