Lokalise Security Basics

Overview

Security practices for Lokalise integrations: API token management with scoped permissions, translation content sanitization, CI/CD secret handling, webhook secret verification, and audit logging. Lokalise handles translation strings that may contain user-facing content, interpolation variables, and occasionally PII embedded in keys or values.

Prerequisites

• Lokalise API token provisioned (admin token for audit, scoped tokens for operations)
• Understanding of Lokalise token permission model (read-only vs read-write)
• Secret management infrastructure (GitHub Secrets, AWS Secrets Manager, GCP Secret Manager, or Vault)

Instructions

Step 1: Token Scope Management

Lokalise API tokens are either read-only or read-write. Create separate tokens per use case to enforce least privilege.

import { LokaliseApi } from "@lokalise/node-api";

// Token strategy: separate tokens per context
const TOKENS = {
  // CI download pipeline — read-only token
  ciDownload: process.env.LOKALISE_READ_TOKEN,
  // CI upload pipeline — read-write token
  ciUpload: process.env.LOKALISE_WRITE_TOKEN,
  // Admin operations (contributor management, webhooks) — admin token
  admin: process.env.LOKALISE_ADMIN_TOKEN,
} as const;

function getClient(scope: keyof typeof TOKENS): LokaliseApi {
  const token = TOKENS[scope];
  if (!token) {
    throw new Error(
      `LOKALISE_${scope.toUpperCase()}_TOKEN not set. ` +
      `Generate at https://app.lokalise.com/profile#apitokens`
    );
  }
  return new LokaliseApi({ apiKey: token, enableCompression: true });
}

// Download translations — uses read-only token
const readClient = getClient("ciDownload");
const bundle = await readClient.files().download(projectId, {
  format: "json",
  original_filenames: false,
  bundle_structure: "%LANG_ISO%.json",
});

Step 2: Validate Translation Content

Translation strings may contain interpolation variables, HTML, or user-generated content. Validate before rendering.

interface ValidationIssue {
  key: string;
  severity: "critical" | "warning";
  message: string;
}

function validateTranslation(key: string, value: string): ValidationIssue[] {
  const issues: ValidationIssue[] = [];

  // XSS: Check for script injection in translations
  if (/<script|javascript:|on\w+=/i.test(value)) {
    issues.push({ key, severity: "critical", message: "Potential XSS payload" });
  }

  // Credential leak: Check for secrets in translation values
  if (/(api_key|password|secret|token)\s*[:=]/i.test(value)) {
    issues.push({ key, severity: "critical", message: "Possible credential in value" });
  }

  // Placeholder integrity: Ensure ICU/i18next placeholders are well-formed
  const placeholders = value.match(/\{[^}]+\}|\{\{[^}]+\}\}/g) ?? [];
  for (const p of placeholders) {
    if (/[<>'"]/.test(p)) {
      issues.push({ key, severity: "warning", message: `Suspicious placeholder: ${p}` });
    }
  }

  return issues;
}

// Validate all translations after download
import { readFileSync } from "fs";

function auditTranslationFile(filePath: string): ValidationIssue[] {
  const data: Record<string, string> = JSON.parse(
    readFileSync(filePath, "utf-8")
  );
  return Object.entries(data).flatMap(([key, value]) =>
    validateTranslation(key, value)
  );
}

const issues = auditTranslationFile("./src/locales/de.json");
const critical = issues.filter((i) => i.severity === "critical");
if (critical.length > 0) {
  console.error("CRITICAL security issues found in translations:");
  critical.forEach((i) => console.error(`  ${i.key}: ${i.message}`));
  process.exit(1);
}

Step 3: Webhook Secret Verification

Lokalise sends a random alphanumeric secret in the X-Secret header. Always verify it.

import express from "express";

const WEBHOOK_SECRET = process.env.LOKALISE_WEBHOOK_SECRET!;

function verifyWebhookSecret(
  req: express.Request,
  res: express.Response,
  next: express.NextFunction
): void {
  const secret = req.headers["x-secret"] as string | undefined;

  if (!secret || secret !== WEBHOOK_SECRET) {
    console.error("Webhook secret verification failed", {
      ip: req.ip,
      path: req.path,
      hasSecret: !!secret,
    });
    res.status(401).json({ error: "Invalid webhook secret" });
    return;
  }
  next();
}

Step 4: CI/CD Token Security

# GitHub Actions: use repository secrets, never hardcode tokens
name: Sync Translations
on:
  push:
    branches: [main]
    paths: ['src/locales/en.json']

jobs:
  sync:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Pull translations
        env:
          LOKALISE_API_TOKEN: ${{ secrets.LOKALISE_READ_TOKEN }}
          LOKALISE_PROJECT_ID: ${{ vars.LOKALISE_PROJECT_ID }}
        run: |
          # Token is masked in logs by GitHub Actions
          lokalise2 file download \
            --token "$LOKALISE_API_TOKEN" \
            --project-id "$LOKALISE_PROJECT_ID" \
            --format json \
            --original-filenames=false \
            --bundle-structure "%LANG_ISO%.json" \
            --unzip-to ./src/locales/

Step 5: Scan for Hardcoded Tokens

#!/bin/bash
# scripts/scan-secrets.sh — Run in CI or as pre-commit hook
set -euo pipefail

echo "=== Lokalise Token Security Scan ==="

# Check for hardcoded tokens in source files
HARDCODED=$(grep -rn "X-Api-Token\|apiKey.*['\"][a-f0-9]\{32,\}" \
  --include="*.ts" --include="*.js" --include="*.json" --include="*.yml" \
  src/ .github/ 2>/dev/null \
  | grep -v node_modules \
  | grep -v "process.env\|secrets\.\|vars\.\|\${{" || true)

if [[ -n "$HARDCODED" ]]; then
  echo "FAIL: Potential hardcoded token found:"
  echo "$HARDCODED"
  exit 1
fi

# Verify .env files are gitignored
if ! grep -q "\.env" .gitignore 2>/dev/null; then
  echo "WARN: .env not in .gitignore — add it immediately"
fi

# Check git history for leaked tokens
HISTORY_LEAK=$(git log --all -p --diff-filter=A -- '*.env' '*.env.*' 2>/dev/null \
  | grep -i "LOKALISE_API_TOKEN=" | head -3 || true)

if [[ -n "$HISTORY_LEAK" ]]; then
  echo "CRITICAL: Token found in git history. Rotate immediately."
  echo "  Use 'git filter-repo' to remove, then rotate the token."
  exit 1
fi

echo "PASS: No hardcoded tokens detected"

Step 6: Audit Translation Changes

interface TranslationAuditEntry {
  timestamp: string;
  projectId: string;
  key: string;
  locale: string;
  userId: string;
  action: "create" | "update" | "delete";
  // Never log actual content — may contain PII
  oldLength: number;
  newLength: number;
}

function logTranslationChange(entry: TranslationAuditEntry): void {
  // Ship to your logging backend (Datadog, CloudWatch, etc.)
  console.log(JSON.stringify({
    level: "info",
    event: "translation_change",
    ...entry,
  }));
}

Output

• Scoped token configuration with separate read/write/admin tokens
• Translation content validator catching XSS, credential leaks, and malformed placeholders
• Webhook secret verification middleware for Express
• CI/CD workflow using repository secrets with masked output
• Pre-commit/CI scan script for hardcoded tokens
• Audit logging for translation changes (PII-safe)

Error Handling

Resources

• Lokalise API Authentication
• Lokalise Security
• Webhook Events Reference
• OWASP Secrets Management

Next Steps

For enterprise-level access control with SSO and contributor groups, see lokalise-enterprise-rbac.