LDAP Injection Pattern Regex for JavaScript

What this pattern does

This page provides a comprehensive, battle-tested regular expression for matching ldap injection pattern, ported and verified for JavaScript. In security-sensitive code, using an unverified regex can open the door to both false positives and denial-of-service attacks. The snippet below is ready to drop into your JavaScript project — whether you're validating in an Express middleware, a Next.js API route, or a client-side form.

Javascript Implementation

// LDAP Injection Pattern
// ReDoS-safe | RegexVault — Security > Injection Patterns

const ldapInjectionPatternRegex = /[)(|*\\\x00]|(?:objectclass|objectCategory|objectGUID|samAccountName|userPrincipalName|memberOf)\s*=|(?:\(uid=)|(?:cn=)(?:[^,)]*\*)/i;

function validateLdapInjectionPattern(input: string): boolean {
  return ldapInjectionPatternRegex.test(input);
}

// Example
console.log(validateLdapInjectionPattern("*)(uid=*))(|(uid=*")); // true

Test Cases

When to use this pattern

This pattern is drawn from the Security > Injection Patterns category and carries a ReDoS-safe certification. That matters for JavaScript developers because especially critical in long-running Node.js event loops where a ReDoS vulnerability can block the entire process. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.

Common Pitfalls

Technical Notes

LDAP special characters: ( ) * \ and null byte. Classic injection: *(|(mail=*)) returns all records when injected into a filter. Defense: use LDAP parameter encoding to escape special characters in search filters. RFC 4515 defines the escape sequences.