Code reviewHardcr-g574

Subject Jwt auth vulnerabilityLevel Senior–Staff~28 minCommon in Security interviewsIndustries Software development, Technology

Question

Review this Node.js JWT verification middleware.

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Code to reviewjs

1const jwt = require('jsonwebtoken');2 3function authenticate(req, res, next) {4  const token = req.headers.authorization?.split(' ')[1];5  const header = JSON.parse(Buffer.from(token.split('.')[0], 'base64').toString());6  const decoded = jwt.verify(token, SECRET, { algorithms: [header.alg] });7  req.user = decoded;8  next();9}

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