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Public proof of conceptFix available

CVE-2002-20001

A public proof of concept exists; no exploitation attested.

  • Published2021-11-11
  • WeaknessCWE-400

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC
  1. 2021-11-1119:15CVE publishedNVD

Versions per branch

NVD
F5 f5os-c
BranchAffectedFixed in
1.3≥ 1.3.0, ≤ 1.3.2no fix published
1.6≥ 1.6.0, ≤ 1.6.2no fix published
1.5= 1.5.0no fix published
1.5= 1.5.1no fix published
1.8= 1.8.0no fix published
1.8= 1.8.1no fix published
Hpe arubaos-cxversion to verify
BranchAffectedFixed in
10.9≥ 10.09.0000, < 10.09.000210.09.0002
10.8≥ 10.08.0000, < 10.08.001010.08.0010
10.7≥ 10.07.0000, < 10.07.003010.07.0030
10.6≥ 10.06.0000, < 10.06.018010.06.0180
F5 f5os-a
BranchAffectedFixed in
1.3≥ 1.3.0, ≤ 1.3.2no fix published
1.5≥ 1.5.0, ≤ 1.5.3no fix published
1.8= 1.8.0no fix published

27 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • openssl-1_1openSUSE:Tumbleweedall versions · fixed in 1.1.1m-4.1
  • ssh-auditopenSUSE:Tumbleweedall versions · fixed in 3.2.0-1.1

Vendor advisories

  • ICSA-22-314-10 CISA3 known affected

    Siemens SCALANCE W1750D

    SCALANCE W1750D (JP) (6GK5750-2HX01-1AD0) · SCALANCE W1750D (ROW) (6GK5750-2HX01-1AA0) · SCALANCE W1750D (USA) (6GK5750-2HX01-1AB0)

  • SSA-506569 Siemens ProductCERT3 known affected

    SSA-506569: Multiple Vulnerabilities in SCALANCE W1750D

    SCALANCE W1750D (JP) (6GK5750-2HX01-1AD0) · SCALANCE W1750D (ROW) (6GK5750-2HX01-1AA0) · SCALANCE W1750D (USA) (6GK5750-2HX01-1AB0)

Full record on NVD

Fix

  1. Vendor fix Siemens ProductCERT SSA-506569 · 3 productsUpdate to V8.7.1.11 or later version
  2. Vendor fix CISA ICSA-22-314-10 · 3 productsUpdate to V8.7.1.11 or later version

Detection

read 2026-11-01 01:02 UTC
Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
2021-11-11
Last Modified
2026-09-23
NVD status
Analyzed
GitHub Advisory
GHSA-jx4r-qc68-xjr5

Frequently asked questions

What is CVE-2002-20001?

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.

Is CVE-2002-20001 actively exploited?

Active exploitation of CVE-2002-20001 has not been confirmed. Its EPSS score was 24.6% on 2026-11-04, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2002-20001?

CVE-2002-20001 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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Sources for this record