Q: Who is affected? (Versions/Components)

📦 **Vendor**: Jellyfin. 📉 **Affected Versions**: All versions **prior to 10.7.3**. ✅ **Fixed In**: Version 10.7.3 and above. 🌐 **Component**: Media streaming server functionality.

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

🔓 **Auth**: None required! (Unauthenticated). 🎯 **Config**: Low complexity. 🚀 **Threshold**: Very Low. Any user can trigger the vulnerability via the `imageUrl` parameter without logging in. ⚡ Easy to exploit.

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

📜 **PoC Available**: Yes. 🔗 **Sources**: ProjectDiscovery Nuclei templates & Awesome-POC GitHub repo. 🌍 **Wild Exploit**: Likely high due to simplicity and lack of auth. 🧪 Testable via standard SSRF payloads.

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

✅ **Fixed**: Yes. 📅 **Patch Date**: Published May 5, 2021. 🔄 **Action**: Upgrade Jellyfin to **version 10.7.3 or later**. 📝 **Advisory**: See GitHub Security Advisory GHSA-rgjw-4fwc-9v96.

Question 1

What is this vulnerability? (Essence + Consequences)

Accepted Answer

🚨 **Essence**: Jellyfin < 10.7.3 suffers from an SSRF vulnerability. 🌊 **Consequences**: Attackers can expose internal/external HTTP servers and access resources normally hidden from users via HTTP GET requests.…

Question 2

Root Cause? (CWE/Flaw)

Accepted Answer

🛡️ **Root Cause**: CWE-918 (Server-Side Request Forgery). 💥 **Flaw**: The `imageUrl` parameter in `RemoteImageController.cs` is not properly validated.…

Question 3

Who is affected? (Versions/Components)

Accepted Answer

📦 **Vendor**: Jellyfin. 📉 **Affected Versions**: All versions **prior to 10.7.3**. ✅ **Fixed In**: Version 10.7.3 and above. 🌐 **Component**: Media streaming server functionality.

Question 4

What can hackers do? (Privileges/Data)

Accepted Answer

🕵️ **Action**: Unauthenticated SSRF attacks. 🌐 **Target**: Internal network services, cloud metadata endpoints, or external resources. 🔓 **Data**: Can read content from HTTP servers that are not publicly accessible.…

Question 5

Is exploitation threshold high? (Auth/Config)

Accepted Answer

🔓 **Auth**: None required! (Unauthenticated). 🎯 **Config**: Low complexity. 🚀 **Threshold**: Very Low. Any user can trigger the vulnerability via the `imageUrl` parameter without logging in. ⚡ Easy to exploit.

Question 6

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

Accepted Answer

📜 **PoC Available**: Yes. 🔗 **Sources**: ProjectDiscovery Nuclei templates & Awesome-POC GitHub repo. 🌍 **Wild Exploit**: Likely high due to simplicity and lack of auth. 🧪 Testable via standard SSRF payloads.

Question 7

How to self-check? (Features/Scanning)

Accepted Answer

🔍 **Check**: Scan for Jellyfin instances. 🧪 **Test**: Send SSRF payloads via the `imageUrl` parameter in API requests. 🛠️ **Tools**: Use Nuclei templates (`CVE-2021-29490.yaml`) for automated detection.…

Question 8

Is it fixed officially? (Patch/Mitigation)

Accepted Answer

✅ **Fixed**: Yes. 📅 **Patch Date**: Published May 5, 2021. 🔄 **Action**: Upgrade Jellyfin to **version 10.7.3 or later**. 📝 **Advisory**: See GitHub Security Advisory GHSA-rgjw-4fwc-9v96.

Question 9

What if no patch? (Workaround)

Accepted Answer

🚧 **Workaround**: If upgrading isn't possible, restrict network access to the Jellyfin server. 🛑 Block outbound HTTP requests from the server to internal/private IP ranges.…

Question 10

Is it urgent? (Priority Suggestion)

Accepted Answer

⚠️ **Priority**: Medium-High. 📉 **CVSS**: 5.3 (Medium). 🆘 **Urgency**: Fix ASAP if exposed to the internet. 🛡️ **Reason**: Unauthenticated SSRF is a critical risk for internal network reconnaissance and data leakage.…

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CVE-2021-29490 — AI Deep Analysis Summary

Q1What is this vulnerability? (Essence + Consequences)

Q2Root Cause? (CWE/Flaw)

Q3Who is affected? (Versions/Components)

Q4What can hackers do? (Privileges/Data)

Q5Is exploitation threshold high? (Auth/Config)

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

Q7How to self-check? (Features/Scanning)

Q8Is it fixed officially? (Patch/Mitigation)

Q9What if no patch? (Workaround)

Q10Is it urgent? (Priority Suggestion)

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