Vulnerability · Published Apr 14, 2026 · Assigned by GitHub_M

CVE-2026-39419MaxKB: Sandbox Result Validation Bypass via Tool Output Spoofing

Low 3.1

In plain English

A low-severity injection in MaxKB from 1Panel-dev. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities).

Severity (CVSS 3.1)3.1Low

Exploit odds (30 days)0.2%top 87.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
1Panel-dev	MaxKB	< 2.8.0

Weakness: CWE-74, CWE-693, CWE-290 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N

References

https://github.com/1Panel-dev/MaxKB/security/advisories/GHSA-f3c8-p474-xwfv x_refsource_CONFIRM
https://github.com/1Panel-dev/MaxKB/commit/38c4cfecd065293ede0437f6fa76cf0116591d25 x_refsource_MISC
https://github.com/1Panel-dev/MaxKB/releases/tag/v2.8.0 x_refsource_MISC