CVE-2026-77521

10.0 CRITICAL 1% exploit odds Fix listed Injection

What it is

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.

At a glance

Exploitability: Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
Exploit odds: 1.0% chance of exploitation in the next 30 days (EPSS).
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2026-08-20 20:23 UTC ReservedThe CVE id was reserved by its CNA
2026-09-21 21:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-09-22 14:17 UTC Last updatedMost recent change to the record

Why it ranks here

Exploited in the wild: no, CISA does not list it.
Exploit odds: 1.0% in the next 30 days (EPSS).
Severity: 10.0 CRITICAL (CVSS).
Fix: a patch or advisory is linked.

Details

Published: 2026-09-21 21:17 UTC
Last modified: 2026-09-22 14:17 UTC
Exploit probability: 1.0% · EPSS, next 30 days
Weakness: CWE-78 · OS command injection
Record status: Deferred

Attack profile CVSS 3.1 · 10.0

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None
Scope: Changed
Confidentiality: High
Integrity: High
Availability: High

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-77521.md and follow it. Check whether this project is affected by CVE-2026-77521. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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Fix and advisories

References

NVD record · CVE.org record