Your login isn't secure if you store secrets in plain sight Your login isn't secure if you store secrets in plain sight TL;DR: Never store or compare plain-text passwords TL;DR: Never store or compare plain-text passwords Problems 😔 Data exposure
Weak security
User trust loss
Compliance issues
Easy exploitation
Authentication bypass potential Data exposure Weak security User trust loss Compliance issues Easy exploitation Authentication bypass potential Solutions 😃 Hash user passwords
Use strong algorithms
Salt every hash
Compare hashes safely
Secure your database
Perform regular penetration tests Hash user passwords Use strong algorithms Salt every hash Salt Compare hashes safely Secure your database Perform regular penetration tests penetration tests Context 💬 When you store or compare passwords as plain-text, you expose users to unnecessary risk. A data breach will instantly reveal every credential. Attackers can reuse these passwords on other sites. Even internal logs or debugging can leak sensitive data. You must treat passwords as secrets, not as values to display or compare directly. Sample Code 📖 Wrong ❌ // Borrowed from "Beyond Vibe Coding"

app.post('/login', async (req, res) => {
  const { username, password } = req.body;
  const user = await Users.findOne({ username });
  if (!user) return res.status(401).send("No such user");
  if (user.password === password) {
    res.send("Login successful!");
  } else {
    res.status(401).send("Incorrect password");
  }
}); // Borrowed from "Beyond Vibe Coding"

app.post('/login', async (req, res) => {
  const { username, password } = req.body;
  const user = await Users.findOne({ username });
  if (!user) return res.status(401).send("No such user");
  if (user.password === password) {
    res.send("Login successful!");
  } else {
    res.status(401).send("Incorrect password");
  }
}); Right 👉 import bcrypt from 'bcrypt';

app.post('/login', async (req, res) => {
  const { username, password } = req.body;
  const user = await Users.findOne({ username });
  if (!user) return res.status(401).send('Invalid credentials');
  const valid = await bcrypt.compare(password, user.password);
  if (!valid) return res.status(401).send('Invalid credentials');
  res.send('Login successful');
}); import bcrypt from 'bcrypt';

app.post('/login', async (req, res) => {
  const { username, password } = req.body;
  const user = await Users.findOne({ username });
  if (!user) return res.status(401).send('Invalid credentials');
  const valid = await bcrypt.compare(password, user.password);
  if (!valid) return res.status(401).send('Invalid credentials');
  res.send('Login successful');
}); Detection 🔍 Semi-Automatic Semi-Automatic You can detect this smell when you see passwords handled as raw strings, compared directly with ===, or stored without hashing. Static analyzers and linters can catch unsafe password handling, but code reviews remain the best defense. Tags 🏷️ Security Security Level 🔋 Beginner Beginner Why the Bijection Is Important 🗺️ In the MAPPER, passwords represent sensitive user credentials that must remain confidential. MAPPER The bijection breaks when you store passwords as plain-text because real-world security expectations don't match your system's actual protection. Users trust you to protect their credentials. When you store plain-text passwords, you create a false representation where the system appears secure but actually exposes sensitive data. This broken mapping between user expectations and system reality leads to security breaches and loss of trust. When you design your authentication system, you create a mapping between a MAPPER concept — a "user’s identity" — and your program’s data. MAPPER Hashing preserves that bijection safely. When you break it by storing raw passwords, your system represents users incorrectly: it turns their private identity into an exposed string. That breaks trust and control. AI Generation 🤖 AI code generators sometimes create login examples comparing plain-text passwords. The code sample is from the book Beyond Vibe Coding in the chapter about "8. Security, Maintainability, and Reliability". Beyond Vibe Coding These examples look simple, but they spread insecure habits. You must always validate and adapt AI-generated authentication code. AI Detection 🧲 AI tools can detect this smell when you provide context about security requirements. They recognize patterns of plain-text password comparison and can suggest proper hashing implementations. You need to ask AI to review the authentication code for security vulnerabilities to get comprehensive fixes. Try Them! 🛠 Remember: AI Assistants make lots of mistakes Remember: AI Assistants make lots of mistakes Suggested Prompt: Refactor this login code to securely hash and compare passwords Suggested Prompt: Refactor this login code to securely hash and compare passwords Without Proper Instructions

With Specific Instructions



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With Specific Instructions



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Qwen Qwen Qwen Qwen Qwen Qwen Qwen Conclusion 🏁 Plain text passwords are a trap. You make your users unsafe and invite catastrophic leaks. You must always hash, salt, and compare securely. The fix is simple, and the trust you earn is priceless. Relations 👩‍❤️‍💋‍👨 https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xxxviii https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xxxviii https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xx-we-have-reached-100 https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xx-we-have-reached-100 https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xliii https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xliii https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xxxiv?embedable=true https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xxxiv?embedable=true https://hackernoon.com/code-smell-258-the-dangers-of-hardcoding-secrets https://hackernoon.com/code-smell-258-the-dangers-of-hardcoding-secrets https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xxxiv?embedable=true https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xxxiv?embedable=true https://hackernoon.com/code-smell-284-encrypted-functions?embedable=true https://hackernoon.com/code-smell-284-encrypted-functions?embedable=true More Information 📕 https://learning.oreilly.com/library/view/beyond-vibe-coding/9798341634749/ch08.html?embedable=true https://learning.oreilly.com/library/view/beyond-vibe-coding/9798341634749/ch08.html?embedable=true Disclaimer 📘 Code Smells are my opinion. opinion If you think technology can solve your security problems, then you don’t understand the problems and you don’t understand the technology. If you think technology can solve your security problems, then you don’t understand the problems and you don’t understand the technology. Bruce Schneier Bruce Schneier https://hackernoon.com/400-thought-provoking-software-engineering-quotes?embedable=true https://hackernoon.com/400-thought-provoking-software-engineering-quotes?embedable=true This article is part of the CodeSmell Series. https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-i-xqz3evd?embedable=true https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-i-xqz3evd?embedable=true

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