Is CVE-2026-77521 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-77521 being exploited in the wild.

How severe is CVE-2026-77521?

Critical severity, with a CVSS score of 10, published 21 September 2026.

Which products and versions are affected?

1Panel-dev MaxKB prior to 2.10.5-lts.

Is there a fix for CVE-2026-77521?

A patch was published on 2026-08-06: v2.10.5-lts release with sandbox command building and command splitting fixes Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-77521 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-77521?

Check whether you run 1Panel-dev MaxKB at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-77521: MaxKB command execution in SandboxShellBackend

CVE-2026-77521 · Severity: critical · CVSS 10 · Published 2026-09-21

MaxKB is an open-source AI assistant platform that allows organizations to build intelligent chatbots. Prior to version 2.10.5-lts, the system failed to properly restrict shell command execution in assistant tools, allowing untrusted chat messages or uploaded content to trigger arbitrary commands. In deployments with sandboxing disabled, commands run with application user privileges; in containerized setups, shell metacharacters could escape the sandbox entirely, enabling complete system compromise.

Technologies: 1Panel-dev MaxKB. Vendors: 1Panel-dev.

Quick answers

Is CVE-2026-77521 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-77521 being exploited in the wild.
How severe is CVE-2026-77521?: Critical severity, with a CVSS score of 10, published 21 September 2026.
Which products and versions are affected?: 1Panel-dev MaxKB prior to 2.10.5-lts.
Is there a fix for CVE-2026-77521?: A patch was published on 2026-08-06: v2.10.5-lts release with sandbox command building and command splitting fixes Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-77521 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-77521?: Check whether you run 1Panel-dev MaxKB at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The SandboxShellBackend did not exclude the execute shell tool from the assistant's available actions and failed to add it to an interrupt list requiring human approval, allowing LLM-controlled command execution. The vulnerability affects tools, MCP tools, skills, and sub-applications that use this backend. Root-cause fixes involved implementing command splitting (via shlex) and proper sandbox command construction to prevent shell metacharacter injection.

Affected products

1Panel-dev MaxKB prior to 2.10.5-lts

Timeline

2026-09-21: disclosed
2026-08-06: patched: v2.10.5-lts release with sandbox command building and command splitting fixes

References

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