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CVE-2002-20001 is a denial-of-service weakness in Diffie-Hellman key agreement, particularly ephemeral finite-field Diffie-Hellman (DHE/EDH) use in TLS and related protocols. A remote client can send arbitrary values that are not valid public keys but still cause the server to perform expensive Diffie-Hellman modular-exponentiation work. This creates a highly asymmetric attack: the client expends minimal CPU time and bandwidth while forcing disproportionate server-side computation. The issue is especially disruptive when the attacker can negotiate DHE and induce the server to use larger supported DH groups or key sizes. The basic scenario described in the source material requires that the client advertise only DHE-compatible options and that the server be configured to permit DHE key exchange.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).
This repository contains D(HE)ater, a proof-of-concept tool for the D(HE)at attack (CVE-2002-20001), which targets TLS and SSH servers supporting Diffie-Hellman Ephemeral (DHE) key exchange. The main exploit logic is implemented in 'dheater/__main__.py', which provides a command-line interface to initiate multiple DHE handshakes against a specified server, thereby causing high CPU usage and potentially leading to denial of service. The tool supports both TLS and SSH protocols and can be configured for different key sizes and thread counts. The repository includes various DH parameter files, test scripts, and setup files. The attack vector is network-based, requiring access to the target server's TLS or SSH service. The tool is written in Python and is intended for research and demonstration purposes.
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6 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A resource exhaustion attack affecting DHE-based TLS handshakes, cited here as a reason to exclude DHE-RSA cipher suites from the recommended intermediate TLS configuration.
A denial-of-service vulnerability in TLS and related protocols where DH/ECDH key exchange support can be abused to cause disproportionate CPU consumption on servers.
A denial-of-service vulnerability referenced in the context of earlier-than-TLS-1.3 Diffie-Hellman parameter generation issues.
A denial-of-service vulnerability affecting Diffie-Hellman protocol variants using ephemeral keys, where attackers can send arbitrary values that are not valid public keys and trigger expensive modular exponentiation on the victim side.
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Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.