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A buffer overflow vulnerability exists in Microsoft IIS 4.0 when processing malformed requests for files with .HTR, .IDC, or .STM extensions. The vulnerability is triggered by sending a specially crafted request that overflows a buffer in the IIS service, leading to a denial of service condition.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (4 hidden).
This repository contains a single Metasploit module (Ruby file) that exploits a buffer overflow vulnerability in the ISAPI ISM.DLL used for HTR scripting in Microsoft IIS 4.0 (CVE-1999-0874). The exploit targets Windows NT 4.0 Service Packs 3, 4, and 5, and allows remote code execution with SYSTEM privileges via a specially crafted HTTP GET request to a .htr file. The module is operational and allows the user to select a payload, which is alpha-numerically encoded to bypass input filters. The exploit requires network access to TCP port 80 on the target. The file is structured as a standard Metasploit exploit module, with configuration options for the target and payload, and implements the exploit logic in the 'exploit' method. No hardcoded IPs or domains are present; the exploit is generic and targets any vulnerable IIS 4.0 instance accessible over the network.
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