User input in format string detected.

• Rule ID: javascript_lang_format_string_using_user_input
• Languages: javascript
• Source: format_string_using_user_input.yml

Description

If an application includes user input directly in a format string, an attacker can use format specifiers in the user input to produce misleading or fabricated messages.

Remediations

❌ Avoid format strings containing user input:

console.log(`The value was ${req.params.value}`)

✅ Use a literal format string with additional arguments:

console.log("The value was %s", req.params.value)

Associated CWE

• CWE-134: Use of Externally-Controlled Format String