RCE in 1panel-Dev Maxkb
CVE-2026-77521
MaxKB is an open-source AI assistant for enterprise. Prior to version 2.10.5-lts, assistants with a tool, MCP tool, skill, or sub-application use SandboxShellBackend, which exposes an execute shell tool without excluding it and omits execute from interrupt_on, so human approval is not required. Untrusted chat or ingested content can therefore cause command execution; source deployments with MAXKB_SANDBOX disabled run commands directly as the application user, while the official root container's string-based gosu wrapper allowed shell metacharacters to execute outside the intended sandbox. This issue is fixed in version 2.10.5-lts.
Vulnerability class: Command Injection (OS Command Injection)
CVSS v3 metric
CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.
Affected products
- 1panel-dev Maxkb — versions < 2.10.5-lts
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-77521?
- CVE-2026-77521 is a critical-severity vulnerability in 1panel-Dev Maxkb, classified under OS Command Injection. CVSS score: 10.0/10. Published 2026-09-21.
- How severe is CVE-2026-77521?
- Critical severity. CVSS v3 base score is 10.0 out of 10.