CVE-2026-39419

MaxKB is an open-source AI assistant for enterprise. In versions 2.7.1 and below, an authenticated user can bypass sandbox result validation and spoof tool execution results by exploiting Python frame introspection to read the wrapper's UUID from its bytecode constants, then writing a forged result directly to file descriptor 1 (bypassing stdout redirection). By calling sys.exit(0), the attacker terminates the wrapper before it prints the legitimate output, causing the MaxKB service to parse and trust the spoofed response as the genuine tool result. This issue has been fixed in version 2.8.0.

CVSS 3.1

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

EPSS

0.2% chance of exploitation in the next 30 days; higher than 12% of CVEs (scores of 2026-10-26)

CWEs

CWE-74, CWE-290, 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/38c4cfecd065293ede0437f6fa76cf0116591d25
• https://github.com/1Panel-dev/MaxKB/releases/tag/v2.8.0
• https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-f3c8-p474-xwfv

Check your stackJSON