CVE-2003-0225: The ASP function Response.AddHeader in Microsoft Internet Information Server (IIS) 4.0 and 5.0 does not lim...

Security readout for executives and security teams

This is an old IIS availability flaw. On IIS 4.0 and 5.0, an ASP page using Response.AddHeader could be abused to make the server allocate excessive memory while building HTTP headers, causing denial of service. It is not described as data theft or code execution. Exposure is mainly legacy IIS 4.0 or 5.0 systems serving ASP pages, especially internet-facing applications where untrusted input can influence response headers. The provided sources do not identify modern IIS versions as affected. Treat this as a legacy-system availability risk. It should not outrank modern actively exploited vulnerabilities, but any internet-facing IIS 4.0 or 5.0 service should be addressed quickly because disruption may be remotely triggerable. Mitigation focus: Inventory any IIS 4.0 or 5.0 servers still running ASP applications.; Apply Microsoft guidance and the MS03-018 security update where applicable.; Decommission or isolate unsupported legacy IIS systems where patching is impractical..

Prepared

Jun 30, 2026, 10:42 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.