CVE-2026-39421: CWE-693: Protection Mechanism Failure in 1Panel-dev MaxKB
MaxKB versions 2. 7. 1 and below have a sandbox escape vulnerability in the ToolExecutor component. An authenticated user with workspace privileges can bypass the LD_PRELOAD-based sandbox by exploiting Python's ctypes to make direct kernel system calls. This allows arbitrary code execution, potentially leading to network exfiltration and container compromise. The vulnerability arises because the sandbox blocks mprotect but not pkey_mprotect, enabling executable memory allocation bypass. This issue is fixed in version 2. 8. 0.
AI Analysis
Technical Summary
CVE-2026-39421 affects MaxKB, an open-source AI assistant for enterprise, in versions prior to 2.8.0. The vulnerability is a sandbox escape in the ToolExecutor component, where an attacker with workspace privileges can use Python's ctypes library to execute raw kernel system calls, circumventing the LD_PRELOAD sandbox.so module. The sandbox intercepts key system functions and blocks mprotect with PROT_EXEC, but does not block pkey_mprotect, allowing executable memory allocation and arbitrary code execution. This can lead to full network exfiltration and container compromise. The vulnerability is classified under CWE-693 (Protection Mechanism Failure) and CWE-94 (Code Injection).
Potential Impact
An authenticated attacker with workspace privileges can bypass sandbox protections to execute arbitrary code at the kernel level. This enables potential full network exfiltration and compromise of the container environment running MaxKB. The CVSS score is 6.3 (medium severity), reflecting the network attack vector, low attack complexity, and privileges required. There are no known exploits in the wild at this time.
Mitigation Recommendations
This vulnerability is fixed in MaxKB version 2.8.0. Users should upgrade to version 2.8.0 or later to remediate this issue. Since no official patch link or advisory is provided, confirm upgrade availability from the vendor's official sources. No other mitigations are indicated.
CVE-2026-39421: CWE-693: Protection Mechanism Failure in 1Panel-dev MaxKB
Description
MaxKB versions 2. 7. 1 and below have a sandbox escape vulnerability in the ToolExecutor component. An authenticated user with workspace privileges can bypass the LD_PRELOAD-based sandbox by exploiting Python's ctypes to make direct kernel system calls. This allows arbitrary code execution, potentially leading to network exfiltration and container compromise. The vulnerability arises because the sandbox blocks mprotect but not pkey_mprotect, enabling executable memory allocation bypass. This issue is fixed in version 2. 8. 0.
CVSS v3.1
Score 6.3medium
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-39421 affects MaxKB, an open-source AI assistant for enterprise, in versions prior to 2.8.0. The vulnerability is a sandbox escape in the ToolExecutor component, where an attacker with workspace privileges can use Python's ctypes library to execute raw kernel system calls, circumventing the LD_PRELOAD sandbox.so module. The sandbox intercepts key system functions and blocks mprotect with PROT_EXEC, but does not block pkey_mprotect, allowing executable memory allocation and arbitrary code execution. This can lead to full network exfiltration and container compromise. The vulnerability is classified under CWE-693 (Protection Mechanism Failure) and CWE-94 (Code Injection).
Potential Impact
An authenticated attacker with workspace privileges can bypass sandbox protections to execute arbitrary code at the kernel level. This enables potential full network exfiltration and compromise of the container environment running MaxKB. The CVSS score is 6.3 (medium severity), reflecting the network attack vector, low attack complexity, and privileges required. There are no known exploits in the wild at this time.
Mitigation Recommendations
This vulnerability is fixed in MaxKB version 2.8.0. Users should upgrade to version 2.8.0 or later to remediate this issue. Since no official patch link or advisory is provided, confirm upgrade availability from the vendor's official sources. No other mitigations are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-07T00:23:30.595Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69dd958882d89c981f9c5825
Added to database: 4/14/2026, 1:16:56 AM
Last enriched: 4/21/2026, 6:15:13 AM
Last updated: 5/27/2026, 2:33:49 AM
Views: 102
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