CVE-2020-9490 — AI Deep Analysis Summary

🚨 **Essence**: A crash vulnerability in Apache HTTP Server. 📉 **Consequences**: The 'Push Diary' component crashes when receiving a crafted HTTP/2 request with a malicious 'Cache-Digest' header.…

🛑 **Root Cause**: Improper handling of the 'Cache-Digest' header in HTTP/2 requests. ⚠️ **Flaw**: The server fails to validate or sanitize this specific header value, leading to a crash.…

🎯 **Affected Versions**: Apache HTTP Server **2.4.20** through **2.4.43**. 🌐 **Component**: The core HTTP/2 module handling cache digests. 📦 **Vendor**: Apache Software Foundation.

💣 **Action**: Attackers can trigger a crash (DoS). 🔓 **Privileges**: No privilege escalation mentioned. 📂 **Data**: No data theft or remote code execution indicated. 🚫 **Goal**: Disrupt service availability.

🔓 **Auth**: Likely **No Authentication** required. 🌍 **Config**: Requires the server to support HTTP/2 and handle Cache-Digest headers. 📡 **Access**: Remote exploitation possible if the server is exposed.

📜 **Public Exp**: No specific PoC code provided in the data. 📢 **Status**: References point to mailing list commits and vendor advisories.…

🔍 **Check**: Scan for Apache HTTP Server versions **2.4.20 - 2.4.43**. 📡 **Test**: Send HTTP/2 requests with malformed 'Cache-Digest' headers. 📋 **Log**: Monitor for 'Push Diary' crashes or service restarts.…

✅ **Fixed**: Yes. 📅 **Date**: References indicate fixes committed in **March/April 2021** (svn commits r1073143, r1073454). 📢 **Advisory**: Official security updates released by Apache and vendors (Fedora, Oracle).…

🛡️ **Workaround**: Disable HTTP/2 if not strictly necessary. 🚫 **Filter**: Block or sanitize 'Cache-Digest' headers at the WAF/Load Balancer level. 🔄 **Restart**: Monitor and auto-restart the service if a crash occurs.…

⚡ **Priority**: **Medium-High**. 📉 **Risk**: DoS impact on availability. 📅 **Urgency**: Patch available since 2021. 🚀 **Action**: Update immediately if running affected versions.…