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CVE-2021-31807 is an integer overflow vulnerability in Squid (before 4.15 and 5.x before 5.0.6) that occurs when processing HTTP Range request headers. A remote server can trigger this flaw by sending a specially crafted Range header in an HTTP response, leading to a use-after-free condition and subsequent crash of the Squid proxy process. The vulnerability is easily triggered by a single malformed header and does not require malicious intent, as the header can appear in normal HTTP traffic.
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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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Cross-references every affected SKU, including bundled OEM variants.
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