Back to CVE records
Medium 6.3Published Apr 13, 2026

CVE-2026-39421MaxKB: Sandbox escape via ctypes and unhooked SYS_pkey_mprotect

Updated under an hour ago ()

Does this affect you?

It affects 1Panel-dev MaxKB and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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
6.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
Weakness (CWE)
CWE-693, CWE-94
Known exploited
Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days)
Not loaded for this CVE
Assigned by
GitHub_M
NVD analysis
Analyzed
Record last updated
Apr 14, 2026
First seen by InfoSec Signals
Oct 9, 2026

Affected products

Affected products
1Panel-dev MaxKB
1panel_dev:maxkb (from the name)
before 2.8.0
CNA record
maxkb maxkb
maxkb:maxkb
before 2.8.0
NVD

References

References

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.

Your cookie choices
We use essential cookies to run this site, and, only with your consent, an advertising cookie from Google to measure whether our ads lead to sign-ups and subscriptions. See our for details.