Vulnerability · CVE-2026-39421
MaxKB is an open-source AI assistant for enterprise.
Published Apr 14, 2026 · catalog updated Jun 17, 2026 · MaxKB is an open-source
Check if you run it
No confirmed exploitation is on record for CVE-2026-39421. EPSS is 0.45%. Act only if a listed version of MaxKB is an open-source is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (MaxKB is an open-source).
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- High7.4
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.45%
- Remediation
- Advisory link
- Affected products
- cpe maxkb/maxkb
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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe maxkb/maxkbversion unspecified
How to fix CVE-2026-39421
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-39421. EPSS is 0.45%. Act only if a listed version of MaxKB is an open-source is installed.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-693: Protection Mechanism Failure; CWE-94: Code Injection. EPSS 0.45%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Apr 14, 2026 · NIST NVD
Detected
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 n
Jun 17, 2026 · NIST NVD
Updated
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 n
Sources
- CVE.orgVulnerability recordCVE-2026-39421
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-39421
30-day exploitation probability 0.4%
first.org - NIST NVDVulnerability recordCVE-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 th
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.