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CVE-2021-31806 is a memory-management vulnerability in Squid (prior to 4.15 and 5.x before 5.0.6) that allows remote attackers to crash the proxy by sending HTTP requests with unsatisfiable 'Range' header values. The flaw is triggered during the processing of these malformed Range requests, leading to a denial of service for all clients using the proxy.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.
This repository contains a single Metasploit auxiliary module (modules/auxiliary/dos/http/squid_range_dos.rb) designed to exploit denial-of-service vulnerabilities in the Squid Proxy server (CVE-2021-31806 and CVE-2021-31807). The module sends specially crafted HTTP requests with malicious Range headers to the target Squid proxy, causing assertion failures and crashing the service. The exploit is configurable for the number of requests and which CVE to target. The code is written in Ruby and leverages Metasploit's HTTP client/server mixins. The only fingerprintable endpoint is the target Squid proxy's HTTP service, typically running on port 3128. The exploit is operational and can be used to test or demonstrate the DoS condition on vulnerable Squid Proxy versions.
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1 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
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Every observed campaign linking this CVE to a named adversary.
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Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.