threat-modeling.md

Threat Model Analysis for alibaba/tengine

Threat: Buffer Overflow in Custom Module

Description: An attacker exploits a buffer overflow vulnerability within a custom Tengine module. By sending crafted requests, the attacker overflows a buffer in the module's code, leading to arbitrary code execution on the server and potentially full system control. Impact:

• Critical: Full system compromise, data breach, service disruption, malware installation, defacement. Affected Tengine Component:
• Specific custom Tengine module (e.g., ngx_http_custom_module). Vulnerability resides in the module's C code. Risk Severity: Critical Mitigation Strategies:
• Implement secure coding practices for custom modules, including input validation and bounds checking.
• Conduct thorough code reviews and static analysis of custom modules.
• Perform fuzz testing on custom modules.
• Regularly audit custom modules and Tengine configuration.
• Consider module sandboxing if feasible.

Threat: Integer Overflow in Session Sticky Logic

Description: An attacker exploits an integer overflow in Tengine's session sticky module. By manipulating session identifiers, they trigger an overflow in session hashing, leading to predictable session routing. This allows session hijacking and bypassing load balancing to target specific backend servers. Impact:

• High: Session hijacking, unauthorized access to user accounts, potential backend server overload, data manipulation. Affected Tengine Component:
• Tengine's session sticky module (ngx_http_upstream_session_sticky_module). Vulnerability is in integer arithmetic within the module. Risk Severity: High Mitigation Strategies:
• Ensure robust integer handling in session sticky module code, including overflow checks.
• Validate session identifiers to prevent malicious overflow-triggering inputs.
• Keep Tengine updated for session sticky related security patches.
• Conduct penetration testing targeting session sticky features.
• Evaluate alternative session management to reduce reliance on session sticky.

Threat: Dynamic Module Loading Vulnerability

Description: An attacker exploits a vulnerability in Tengine's dynamic module loading mechanism. This could allow loading malicious modules by bypassing authentication or exploiting flaws in the loading process itself. Successful exploitation grants arbitrary code execution and server control. Impact:

• Critical: Arbitrary code execution, full system compromise, backdoor installation, service disruption. Affected Tengine Component:
• Tengine's dynamic module loading functionality and load_module directive. Vulnerability could be in core Tengine code or configuration parsing. Risk Severity: Critical Mitigation Strategies:
• Disable dynamic module loading if unnecessary. Restrict loading to trusted sources if required.
• Implement strong access controls on Tengine configuration and module directories.
• Regularly audit dynamic module loading configuration and process.
• Apply principle of least privilege to Tengine processes.
• Monitor Tengine logs for unauthorized module loading attempts.

Threat: Regression of Nginx Security Patch

Description: Tengine fails to incorporate a critical security patch from upstream Nginx. An attacker exploits a known Nginx vulnerability present in the outdated Tengine version. This allows exploitation of the known Nginx vulnerability against the Tengine server. Impact:

• High to Critical: Impact depends on the specific Nginx vulnerability, potentially leading to information disclosure or arbitrary code execution. Affected Tengine Component:
• Core Tengine code based on outdated Nginx, lacking the security patch. Risk Severity: High to Critical (Severity depends on the specific Nginx vulnerability) Mitigation Strategies:
• Regularly update Tengine to incorporate upstream Nginx security patches promptly.
• Monitor Nginx security advisories and check Tengine version impact.
• Regularly scan Tengine servers for known Nginx vulnerabilities.
• Consider using upstream Nginx if timely security patching is paramount.

Threat: Outdated Tengine Version - Known Vulnerabilities

Description: Running an outdated and unpatched Tengine version exposes the application to publicly known vulnerabilities. Attackers exploit these vulnerabilities, often with readily available exploit code, leading to server compromise. Impact:

• High to Critical: Impact depends on the specific vulnerabilities in the outdated Tengine version, potentially leading to information disclosure or arbitrary code execution. Affected Tengine Component:
• Entire Tengine installation due to vulnerabilities in the outdated codebase. Risk Severity: High to Critical (Severity depends on the specific vulnerabilities in the outdated version) Mitigation Strategies:
• Maintain a strict patching schedule and update Tengine to the latest stable version promptly.
• Regularly scan Tengine servers for known vulnerabilities.
• Implement automated patch management for timely security updates.
• Implement security monitoring to detect exploitation attempts targeting known vulnerabilities.