CWE-795: Only Filtering Special Elements at a Specified Location
Learn about CWE-795 (Only Filtering Special Elements at a Specified Location), its security impact, exploitation methods, and prevention guidelines.
What is Only Filtering Special Elements at a Specified Location?
• Overview: This vulnerability occurs when a software system filters or sanitizes special elements in data only at specific locations, such as a specific byte position or relative to a particular marker. This incomplete filtering can leave other instances of these special elements unchecked and potentially dangerous.
• Exploitation Methods:
- Attackers can exploit this by inserting malicious data outside the specified filtered locations, which may bypass security controls.
- Common attack patterns include injecting special characters or code at positions not checked by the filter, such as SQL injection, cross-site scripting (XSS), or path traversal attacks.
• Security Impact:
- Direct consequences of successful exploitation include unauthorized data access, data manipulation, and execution of malicious code.
- Potential cascading effects involve further breaches within the system, allowing attackers to escalate privileges or compromise additional components.
- Business impact can range from data breaches and loss of customer trust to financial losses and regulatory penalties.
• Prevention Guidelines:
- Specific code-level fixes include implementing comprehensive filtering and validation that checks all input data regardless of position.
- Security best practices involve adopting a whitelist approach to input validation and ensuring that all special elements are accounted for globally.
- Recommended tools and frameworks include input validation libraries, security-focused static analysis tools, and frameworks that provide built-in protection against common vulnerabilities.
Technical Details
Likelihood of Exploit: Not specified
Affected Languages: Not specified
Affected Technologies: Not specified