HashiCorp Vault Token Regex for JavaScript

What this pattern does

This page provides a well-structured, multi-part regular expression for matching hashicorp vault token, 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

// HashiCorp Vault Token
// ReDoS-safe | RegexVault — Security > Secrets & Config

const hashicorpVaultTokenRegex = /^(?:hvs\.|s\.)[A-Za-z0-9]{20,200}$/;

function validateHashicorpVaultToken(input: string): boolean {
  return hashicorpVaultTokenRegex.test(input);
}

// Example
console.log(validateHashicorpVaultToken("hvs.CAESILdJHHVdRKmXpGGNVRpzuIMz8NuNEMFWMJ0ZjUVNxWqp")); // true

Test Cases

When to use this pattern

This pattern is drawn from the Security > Secrets & Config 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

Vault tokens: older format uses s. prefix; newer (Vault 1.10+) uses hvs. for service tokens, hvb. for batch tokens, hvr. for recovery tokens. Tokens expire based on TTL and are linked to specific Vault policies. Revoke via vault token revoke if exposed.