CVE-2026-39421

MaxKB is an open-source AI assistant for enterprise. Versions 2.7.1 and below contain a sandbox escape vulnerability in the ToolExecutor component. By leveraging Python's ctypes library to execute raw system calls, an authenticated attacker with workspace privileges can bypass the LD_PRELOAD-based sandbox.so module to achieve arbitrary code execution via direct kernel system calls, enabling full network exfiltration and container compromise. The library intercepts critical standard system functions such as execve, system, connect, and open. It also intercepts mprotect to prevent PROT_EXEC (executable memory) allocations within the sandboxed Python processes, but pkey_mprotect is not blocked. This issue has been fixed in version 2.8.0.

CVSS v3 6.3 MEDIUM

6.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/1Panel-dev/MaxKB/commit/479701a4d2e6059506bad0057a66bed91abb5aef	Patch
https://github.com/1Panel-dev/MaxKB/releases/tag/v2.8.0	Release Notes
https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-9c6w-j7w5-3gf7	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:maxkb:maxkb:*:*:*:*:-:*:*:*

History

No history.

Information

Published : 2026-04-14 01:16

Updated : 2026-06-17 10:42

NVD link : CVE-2026-39421

Mitre link : CVE-2026-39421

CVE.ORG link : CVE-2026-39421

JSON object : View

Products Affected

maxkb

maxkb

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

CWE-693

Protection Mechanism Failure

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