Vulnerability Information

AppSecAI Vulnerability ID: 69654fbefc355c4beda09b62
Vulnerability: Command Injection
CWE Classification: CWE-78
Severity: High
File: src/main/java/org/owasp/benchmark/testcode/BenchmarkTest02244.java
Detection Rule: java.lang.security.audit.tainted-cmd-from-http-request.tainted-cmd-from-http-request
Description: Detected input from a HTTPServletRequest going into a 'ProcessBuilder' or 'exec' command. This could lead to command injection if variables passed into the exec commands are not properly sanitized. Instead, avoid using these OS commands with user-supplied input, or, if you must use these commands, use a whitelist of specific values.

Triage Analysis

Status: Confirmed vulnerability
Security Assessment:

Severity: Critical

Confidence: 100%

Analysis

User input from HTTP request parameter 'BenchmarkTest02244' flows through doSomething() to 'bar', which is directly concatenated into a shell command ('echo ' + bar). The code explicitly invokes a shell (sh -c or cmd.exe /c) and passes the concatenated string as a command argument. This allows shell metacharacters (;, |, &&, backticks) in the user input to execute arbitrary commands. For example, input 'test; whoami' would execute both 'echo test' and 'whoami'. While ProcessBuilder with a List is used, the protection is negated by invoking the shell with the -c flag, which interprets the third argument as a shell command. No input validation or sanitization is present.

Recommended Remediation

Remove the shell invocation entirely and execute commands directly. If echo functionality is required, implement it without shell interpretation. If dynamic command execution is necessary, implement a strict allowlist of permitted commands and validate all parameters against alphanumeric-only patterns. Never concatenate user input into shell commands passed to sh -c or cmd.exe /c.

Remediation Details

Fix Description:

Fix Summary

Fixed the command injection vulnerability by implementing input validation with a whitelist approach. The original code concatenated unsanitized user input directly into a shell command string ("echo " + bar), allowing attackers to inject arbitrary commands using shell metacharacters (e.g., ; rm -rf /).

The fix validates the bar variable against a whitelist regex pattern that allows only:

• Alphanumeric characters (a-zA-Z0-9)
• Spaces
• Basic safe punctuation (. , _ -)

Any input containing shell metacharacters (;, |, &, $, backticks, quotes, redirections, etc.) is rejected before reaching the ProcessBuilder, preventing command injection attacks. The validation occurs immediately after retrieving the user input and before constructing the command, ensuring malicious input never reaches the vulnerable code path.

The fix maintains complete API compatibility and functional equivalence - legitimate input continues to work exactly as before, while malicious input is safely rejected.

Migration Steps Required:

None. This is a self-contained security fix that requires no configuration changes, database migrations, or deployment coordination. The change is 100% backward compatible with existing legitimate usage patterns.

Testing:

• Verify legitimate input (alphanumeric + spaces + basic punctuation) continues to work
• Test that shell metacharacters are properly rejected: ; ls, | cat /etc/passwd, & whoami, $(id), etc.
• Confirm error message is displayed to users when invalid input is detected
• Validate that the echo command still functions correctly with safe input

Changes Made:

• Updated source code with secure implementation

This PR was generated automatically to address a security vulnerability.
Please review the changes carefully before merging.