{"id":"CVE-2002-20001","url":"https://www.cyber-defence.io/tools/cve/CVE-2002-20001","generatedAt":"2026-11-05T00:59:06.134Z","title":"The Diffie-Hellman Key Agreement Protocol allows remote attackers (from the client side) to send arbitrary numbers that are actually not public keys, and trigger expensive server-side DHE modular-exponentiation calculations, aka a D(HE)at or D(HE)ater…","description":"The Diffie-Hellman Key Agreement Protocol allows remote attackers (from the client side) to send arbitrary numbers that are actually not public keys, and trigger expensive server-side DHE modular-exponentiation calculations, aka a D(HE)at or D(HE)ater attack. The client needs very little CPU resources and network bandwidth. The attack may be more disruptive in cases where a client can require a server to select its largest supported key size. The basic attack scenario is that the client must claim that it can only communicate with DHE, and the server must be configured to allow DHE.","published":"2021-11-11T19:15:07.000Z","lastModified":"2026-09-23T13:10:00.000Z","status":"Analyzed","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-400"],"affected":["balasys/dheater","siemens/scalance w1750d firmware","suse/linux enterprise server","f5/big-ip access policy manager","f5/big-ip advanced firewall manager","f5/big-ip advanced web application firewall","f5/big-ip analytics","f5/big-ip application acceleration manager","f5/big-ip application security manager","f5/big-ip application visibility and reporting","f5/big-ip carrier-grade nat","f5/big-ip ddos hybrid defender","f5/big-ip domain name system","f5/big-ip edge gateway","f5/big-ip fraud protection service","f5/big-ip global traffic manager","f5/big-ip link controller","f5/big-ip local traffic manager","f5/big-ip policy enforcement manager","f5/big-ip service proxy","f5/big-ip ssl orchestrator","f5/big-ip webaccelerator","f5/big-ip websafe","f5/big-iq centralized management","f5/traffix signaling delivery controller","f5/f5os-a","f5/f5os-c","hpe/arubaos-cx","stormshield/stormshield management center","stormshield/stormshield network security"],"epss":{"score":0.24639,"percentile":0.97891,"date":"2026-11-03","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"EPSS puts the probability of exploitation in the next 30 days at 24.6%, higher than 98% of all known CVEs. Patch or mitigate before the next change window."},"changes":[],"references":[{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-506569.pdf","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://dheatattack.com","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://dheatattack.gitlab.io/","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/Balasys/dheater","tags":["Product","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/mozilla/ssl-config-generator/issues/162","tags":["Issue Tracking"],"source":"cve@mitre.org"},{"url":"https://gitlab.com/dheatattack/dheater","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://ieeexplore.ieee.org/document/10374117","tags":["Technical Description","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://support.f5.com/csp/article/K83120834","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://www.arubanetworks.com/assets/alert/ARUBA-PSA-2022-004.txt","tags":["Technical Description","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://www.openssl.org/blog/blog/2022/10/21/tls-groups-configuration/","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://www.reddit.com/r/netsec/comments/qdoosy/server_overload_by_enforcing_dhe_key_exchange/","tags":["Issue Tracking"],"source":"cve@mitre.org"},{"url":"https://www.researchgate.net/profile/Anton-Stiglic-2/publication/2401745_Security_Issues_in_the_Diffie-Hellman_Key_Agreement_Protocol","tags":["Exploit","Technical Description"],"source":"cve@mitre.org"},{"url":"https://www.suse.com/support/kb/doc/?id=000020510","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-506569.pdf","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://dheatattack.com","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://dheatattack.gitlab.io/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/Balasys/dheater","tags":["Product","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/mozilla/ssl-config-generator/issues/162","tags":["Issue Tracking"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://gitlab.com/dheatattack/dheater","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://ieeexplore.ieee.org/document/10374117","tags":["Technical Description","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.f5.com/csp/article/K83120834","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.arubanetworks.com/assets/alert/ARUBA-PSA-2022-004.txt","tags":["Technical Description","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.openssl.org/blog/blog/2022/10/21/tls-groups-configuration/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.reddit.com/r/netsec/comments/qdoosy/server_overload_by_enforcing_dhe_key_exchange/","tags":["Issue Tracking"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.researchgate.net/profile/Anton-Stiglic-2/publication/2401745_Security_Issues_in_the_Diffie-Hellman_Key_Agreement_Protocol","tags":["Exploit","Technical Description"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.suse.com/support/kb/doc/?id=000020510","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2002-20001","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}