CVE-2026-77521

CRITICAL 10.0CVE-2026-77521 · Published 21/09/2026 · updated 22/09/2026

In short

CVE-2026-77521 is a CRITICAL (CVSS 10.0) vulnerability.
Chance of exploitation in the next 30 days (EPSS): 1.0%, higher than 64.3% of all vulnerabilities.
No patched version is listed yet: follow the vendor's advisory in References.

Package	Affected versions	Patched versions
—	No affected product versions are listed for this vulnerability yet.

Description

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.

References

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