CVE-2020-5284 — AI Deep Analysis Summary

Q: What is this vulnerability? (Essence + Consequences)

🚨 **Essence**: Path Traversal in Next.js < 9.3.2. 📉 **Consequences**: Attackers can access files outside the intended `.next/dist` directory. Sensitive internal build assets are exposed! 📂

Q: Root Cause? (CWE/Flaw)

🛡️ **CWE-23**: Improper Restriction of File Path. 🐛 **Flaw**: The framework fails to filter special characters in resource/file paths. Input validation is missing! ❌

Q: Who is affected? (Versions/Components)

👥 **Affected**: ZEIT Next.js versions **before 9.3.2**. 📦 **Component**: The static file serving mechanism in the development/build output. ⚠️

Q: What can hackers do? (Privileges/Data)

🕵️ **Action**: Local File Inclusion (LFI). 📄 **Data**: Access to files within the `.next` directory. 💣 **Note**: Generally limited to build assets, unless custom assets are stored there. 📉

Q: Is exploitation threshold high? (Auth/Config)

🔑 **Threshold**: Medium. 🌐 **Network**: Remote (AV:N). 🔒 **Auth**: Low Privileges required (PR:L). 🖱️ **UI**: User Interaction required (UI:R). 📉 **Complexity**: High (AC:H).

Q: Is there a public Exp? (PoC/Wild Exploitation)

💻 **Exploit**: Yes, Public PoC available! 🔗 Links provided in Nuclei templates and Xray plugins. 🌍 **Wild Exploit**: Limited scope (mostly `.next` dir), but easily replicable. 🚀

Q: How to self-check? (Features/Scanning)

🔍 **Check**: Scan for Next.js versions < 9.3.2. 🧪 **Test**: Craft requests with `../` in paths targeting `.next/dist`. 📡 **Tools**: Use Nuclei or Xray templates for automated detection. 🛠️

Q: Is it fixed officially? (Patch/Mitigation)

✅ **Fixed**: Yes! Patched in **v9.3.2**. 🔄 **Action**: Upgrade immediately to the latest stable version. 📥 Check GitHub releases for the fix. 🛡️

Q: What if no patch? (Workaround)

🚧 **Workaround**: If upgrading is impossible, restrict access to the `.next` directory via web server config (Nginx/Apache). 🚫 Block traversal sequences (`../`) at the WAF level. 🛑

Q: Is it urgent? (Priority Suggestion)

⚡ **Urgency**: High Priority. 🚨 CVSS Score indicates remote exploitation with low privileges. 📅 Published in 2020, but legacy systems may still be vulnerable. 🏃♂️ Patch NOW! 🔧

Updated May 08, 2026 CVSS 4.4 · Medium

This is a summary of the AI-generated 10-question deep analysis. The full version (longer answers, follow-up Q&A, related CVEs) requires login. Read the full analysis →

Q1What is this vulnerability? (Essence + Consequences)

🚨 **Essence**: Path Traversal in Next.js < 9.3.2. 📉 **Consequences**: Attackers can access files outside the intended `.next/dist` directory. Sensitive internal build assets are exposed! 📂

Q2Root Cause? (CWE/Flaw)

🛡️ **CWE-23**: Improper Restriction of File Path. 🐛 **Flaw**: The framework fails to filter special characters in resource/file paths. Input validation is missing! ❌

Q3Who is affected? (Versions/Components)

👥 **Affected**: ZEIT Next.js versions **before 9.3.2**. 📦 **Component**: The static file serving mechanism in the development/build output. ⚠️

Q4What can hackers do? (Privileges/Data)

🕵️ **Action**: Local File Inclusion (LFI). 📄 **Data**: Access to files within the `.next` directory. 💣 **Note**: Generally limited to build assets, unless custom assets are stored there. 📉

Q5Is exploitation threshold high? (Auth/Config)

🔑 **Threshold**: Medium. 🌐 **Network**: Remote (AV:N). 🔒 **Auth**: Low Privileges required (PR:L). 🖱️ **UI**: User Interaction required (UI:R). 📉 **Complexity**: High (AC:H).

Q6Is there a public Exp? (PoC/Wild Exploitation)

💻 **Exploit**: Yes, Public PoC available! 🔗 Links provided in Nuclei templates and Xray plugins. 🌍 **Wild Exploit**: Limited scope (mostly `.next` dir), but easily replicable. 🚀

Q7How to self-check? (Features/Scanning)

🔍 **Check**: Scan for Next.js versions < 9.3.2. 🧪 **Test**: Craft requests with `../` in paths targeting `.next/dist`. 📡 **Tools**: Use Nuclei or Xray templates for automated detection. 🛠️

Q8Is it fixed officially? (Patch/Mitigation)

✅ **Fixed**: Yes! Patched in **v9.3.2**. 🔄 **Action**: Upgrade immediately to the latest stable version. 📥 Check GitHub releases for the fix. 🛡️

Q9What if no patch? (Workaround)

🚧 **Workaround**: If upgrading is impossible, restrict access to the `.next` directory via web server config (Nginx/Apache). 🚫 Block traversal sequences (`../`) at the WAF level. 🛑

Q10Is it urgent? (Priority Suggestion)

⚡ **Urgency**: High Priority. 🚨 CVSS Score indicates remote exploitation with low privileges. 📅 Published in 2020, but legacy systems may still be vulnerable. 🏃‍♂️ Patch NOW! 🔧

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Vulnerability detail Full AI analysis (login) zeit CWE-23