CVE-1999-0278 — AI Deep Analysis Summary

🚨 **Essence**: IIS 3.0/4.0 leaks ASP source code via NTFS alternate data streams. 📉 **Consequences**: Attackers get raw code instead of executed HTML, exposing backend logic and secrets.

🛠️ **Root Cause**: IIS checks file extensions for execution. If not found, it serves raw content. It fails to block NTFS stream requests (like `::$DATA`), bypassing the ASP handler.…

🖥️ **Affected**: Microsoft IIS 3.0 and IIS 4.0. 💻 **OS**: Windows NT systems. ⚠️ **Note**: Very old legacy software.

🕵️ **Action**: Remote attackers can retrieve `.asp` source code. 🔓 **Impact**: Exposure of sensitive business logic, database credentials, and internal architecture. No auth needed for the request itself.

📶 **Threshold**: LOW. 🌐 **Auth**: None required. Remote exploitation is possible via standard HTTP requests. ⚙️ **Config**: Default IIS behavior on NTFS drives is vulnerable.

📜 **Exploit**: Yes. Referenced in MS98-003 and OVAL. 🌍 **Wild Exploitation**: High probability given the age and simplicity of the vector (appending `::$DATA` to URLs).

🔍 **Check**: Send HTTP request to `filename.asp::$DATA`. 📥 **Result**: If you receive raw ASP code (e.g., `<% ... %>`) instead of HTML, you are vulnerable.…

🩹 **Fix**: Yes. Microsoft released patch **MS98-003**. 📅 **Published**: Sept 1999. Update IIS or apply the specific security bulletin patch.

🚧 **Workaround**: If patching is impossible, disable NTFS Alternate Data Streams support or restrict access to `.asp` files via firewall/WAF rules blocking `::$DATA` patterns. 🚫 **Best**: Upgrade OS/IIS immediately.

🔥 **Priority**: CRITICAL for legacy systems. 📉 **Current Risk**: Low for modern web, but HIGH if running ancient Windows NT/IIS 4.0. Treat as immediate remediation if found.