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CVE-2011-4858 is an algorithmic-complexity denial-of-service vulnerability in Apache Tomcat form-parameter processing. Affected versions use predictable Java hashCode() values when storing request parameter names, permitting an attacker to construct many distinct names that collide in the same hash bucket. Processing the resulting request can consume excessive CPU resources.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).
This repository contains a single Metasploit auxiliary module: 'modules/auxiliary/dos/http/hashcollision_dos.rb'. The module implements a denial-of-service (DoS) attack that targets web servers written in PHP or Java by exploiting hash table collision vulnerabilities (CVE-2011-5034, CVE-2011-5035, CVE-2011-4885, CVE-2011-4858). The exploit generates a large HTTP POST request with many parameters whose names are crafted to produce identical hash values, causing the server's hash table implementation to consume excessive CPU resources while parsing the request. This can render the web service unresponsive. The module allows the user to select the target type (PHP or Java), customize the request URI, and adjust payload parameters. The code is written in Ruby and is designed to be run within the Metasploit Framework. No hardcoded IP addresses or domains are present; the attack is directed at a user-specified HTTP endpoint (default '/'). The repository is operational and provides a working DoS exploit for the described vulnerability.
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5 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A predictable Java hash-collision denial-of-service issue affecting JBoss Web request parameter processing. The update limits parameters and headers processed per request.
A predictable Java hash-collision denial-of-service issue affecting JBoss Web. Crafted HTTP requests with many colliding parameter names can consume excessive CPU. The update limits processed request parameters and headers.
A predictable Java hash-collision denial-of-service issue in JBoss Web that permits CPU exhaustion through HTTP requests containing many colliding parameter names.
A remotely exploitable denial-of-service vulnerability addressed by HP's update.
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Cross-references every affected SKU, including bundled OEM variants.
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