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 3.1

7.4CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L

EPSS

0.3% chance of exploitation in the next 30 days; higher than 18% of CVEs (scores of 2026-10-26)

CWEs

CWE-94, CWE-693

Published

2026-04-14

Modified

2026-10-26

Record from

the NVD, synced 2026-10-26

Affected

• maxkb:maxkb

References

• https://github.com/1Panel-dev/MaxKB/commit/479701a4d2e6059506bad0057a66bed91abb5aef
• https://github.com/1Panel-dev/MaxKB/releases/tag/v2.8.0
• https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-9c6w-j7w5-3gf7

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