CVE-2002-20001

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2022-04-21. NVD baseline CVSS 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Elevated
7.5EG
EchelonGraph verdictPlan mitigationRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • Public exploit or proof-of-concept code is available
CISA-KEV: Not listedEPSS PROB: 25%CVSS: 7.5Exploit: Public PoCExposed services: Not assessed

No fix is confirmed yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for the fix.

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.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
54
EG Risk 54/100

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed (value × EchelonGraph’s weight)
Severity75% × 45%
The EG Score, 7.5 of 10.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability30% × 15%
EchelonGraph's default: CISA has not published Automatable for this CVE.
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* or Attend at high (mission-essential systems).
Exploitation public PoC (EG-KEV: elevated) · Automatable unknown (not published for this CVE) · Technical impact partial (CVSS below 9.0). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from Vulnrichment. EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.
EPSS PROB
25%
EPSS %ILE
97th
KEV
Not listed

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* or Attend at high (mission-essential systems).

No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.

Exploitation public PoC (EG-KEV: elevated) · Automatable unknown (not published for this CVE) · Technical impact partial (CVSS below 9.0). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from Vulnrichment. EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

Published

November 11, 2021

Last Modified

September 23, 2026

Advisory Details (8)

Auto-updated Jul 24, 2026
🔬 Proof of concept available. No fix on record yet.
generic

Configuring supported TLS groups in OpenSSL | OpenSSL Library

https://www.openssl.org/blog/blog/2022/10/21/tls-groups-configuration/
generic

myF5

https://support.f5.com/csp/article/K83120834
generic🟡 PoC Available

D(HE)at Attack / DHEater · GitLab

https://gitlab.com/dheatattack/dheater
generic🟡 PoC Available

Stop recommending DHE, because of "dheater" vulnerability · Issue #299 · mozilla/server-side-tls · GitHub

https://github.com/mozilla/ssl-config-generator/issues/162
generic🟡 PoC Available

GitHub - c0r0n3r/dheater: D(HE)ater is a proof of concept implementation of the D(HE)at attack (CVE-2002-20001) through which denial-of-service can be performed by enforcing the Diffie-Hellman key exchange. (read-only clone of the original GitLab project) · GitHub

https://github.com/Balasys/dheater
generic

D(HE)at Attack | D(HE)at Attack

https://dheatattack.gitlab.io/
generic

D(HE)at Attack | D(HE)at Attack

https://dheatattack.com
generic
https://cert-portal.siemens.com/productcert/pdf/ssa-506569.pdf

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 6× in last 7d / 11× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 17 repeat rows among the latest 78 are merged into the row they repeat.

  1. 2026-10-10 19:53 UTCEPSS rescoreEPSS 25% · 97th percentile
  2. 2026-10-09 19:58 UTCEPSS rescoreEPSS 25% · 97th percentile
  3. 2026-10-08 16:28 UTCEPSS rescoreEPSS 25% · 97th percentile
  4. 2026-10-07 23:35 UTCEPSS rescoreEPSS 25% · 97th percentile
  5. 2026-10-06 15:08 UTCEPSS rescoreEPSS 25% · 97th percentile
  6. 2026-10-05 17:36 UTCEPSS rescoreEPSS 25% · 97th percentile
  7. 2026-10-03 14:19 UTCEPSS rescoreEPSS 25% · 97th percentile
  8. 2026-09-29 02:37 UTCEG score recompute
  9. 2026-09-23 13:19 UTCEG score recompute
  10. 2026-09-23 13:19 UTCGHSA enrichmentGHSA-jx4r-qc68-xjr5 · GitHub severity HIGH · GitHub CVSS 7.5
  11. 2026-09-12 14:54 UTCEPSS rescoreEPSS 25% · 97th percentile
  12. 2026-09-10 09:23 UTCEPSS rescoreEPSS 25% · 97th percentile
  13. 2026-08-30 01:13 UTCEPSS rescoreEPSS 23% · 97th percentile
  14. 2026-07-25 14:11 UTCEPSS rescoreEPSS 23% · 97th percentile
  15. 2026-07-24 14:11 UTCEPSS rescoreEPSS 23% · 97th percentile
  16. 2026-07-23 00:44 UTCEG score recompute
  17. 2026-07-23 00:26 UTCEG score recompute
  18. 2026-07-22 23:49 UTCEG score recompute
  19. 2026-07-22 21:29 UTCEG score recompute
  20. 2026-07-20 17:02 UTCEPSS rescoreEPSS 23% · 97th percentile
  21. 2026-07-19 14:25 UTCEPSS rescoreEPSS 23% · 97th percentile
  22. 2026-07-18 09:59 UTCEPSS rescoreEPSS 23% · 97th percentile
  23. 2026-07-16 16:58 UTCEPSS rescoreEPSS 23% · 97th percentile
  24. 2026-07-15 01:55 UTCEPSS rescoreEPSS 23% · 97th percentile
  25. 2026-07-11 08:22 UTCEPSS rescoreEPSS 23% · 97th percentile
Show 36 more
  1. 2026-07-08 15:09 UTCEPSS rescoreEPSS 23% · 97th percentile
  2. 2026-07-06 02:19 UTCEPSS rescoreEPSS 23% · 97th percentile
  3. 2026-07-04 06:26 UTCEPSS rescoreEPSS 23% · 97th percentile
  4. 2026-07-02 14:00 UTCEPSS rescoreEPSS 23% · 97th percentile
  5. 2026-06-28 14:02 UTCEPSS rescoreEPSS 23% · 97th percentile
  6. 2026-06-28 04:52 UTCEPSS rescoreEPSS 23% · 97th percentile
  7. 2026-06-27 03:04 UTCEPSS rescoreEPSS 23% · 97th percentile
  8. 2026-06-23 21:29 UTCEPSS rescoreEPSS 23% · 97th percentile
  9. 2026-06-22 14:22 UTCEPSS rescoreEPSS 23% · 97th percentile
  10. 2026-06-21 01:56 UTCEPSS rescoreEPSS 23% · 97th percentile
  11. 2026-06-18 17:49 UTCEPSS rescoreEPSS 23% · 97th percentile
  12. 2026-06-17 17:49 UTCEPSS rescoreEPSS 23% · 97th percentile
  13. 2026-06-16 17:49 UTCEPSS rescoreEPSS 23% · 97th percentile
  14. 2026-06-15 17:43 UTCEPSS rescoreEPSS 23% · 97th percentile
  15. 2026-06-14 23:13 UTCEPSS rescoreEPSS 19% · 95th percentile
  16. 2026-06-13 22:56 UTCEPSS rescoreEPSS 19% · 95th percentile
  17. 2026-06-12 23:08 UTCEPSS rescoreEPSS 19% · 95th percentile
  18. 2026-06-11 13:55 UTCEPSS rescoreEPSS 19% · 95th percentile
  19. 2026-06-10 22:13 UTCEPSS rescoreEPSS 19% · 95th percentile
  20. 2026-06-10 13:17 UTCEPSS rescoreEPSS 19% · 95th percentile
  21. 2026-06-07 15:21 UTCEPSS rescoreEPSS 19% · 95th percentile
  22. 2026-06-06 13:44 UTCEPSS rescoreEPSS 15% · 94th percentile
  23. 2026-06-05 22:43 UTCEPSS rescoreEPSS 15% · 94th percentile
  24. 2026-06-04 13:09 UTCEPSS rescoreEPSS 15% · 94th percentile
  25. 2026-06-02 20:10 UTCEPSS rescoreEPSS 15% · 94th percentile
  26. 2026-06-01 13:49 UTCEPSS rescoreEPSS 15% · 94th percentile
  27. 2026-05-31 22:28 UTCEPSS rescoreEPSS 15% · 94th percentile
  28. 2026-05-31 00:13 UTCEPSS rescoreEPSS 15% · 94th percentile
  29. 2026-05-29 13:40 UTCEPSS rescoreEPSS 15% · 94th percentile
  30. 2026-05-28 13:42 UTCEPSS rescoreEPSS 15% · 94th percentile
  31. 2026-05-27 13:37 UTCEPSS rescoreEPSS 15% · 94th percentile
  32. 2026-05-26 13:41 UTCEPSS rescoreEPSS 15% · 94th percentile
  33. 2026-05-26 07:40 UTCEG score recompute
  34. 2026-05-26 07:40 UTCGHSA enrichmentGHSA-jx4r-qc68-xjr5 · GitHub severity HIGH · GitHub CVSS 7.5
  35. 2026-05-26 07:16 UTCEPSS rescoreEPSS 15% · 94th percentile
  36. 2026-05-24 16:42 UTCEPSS rescoreEPSS 15% · 94th percentile

Publicly available exploits

(1 reference)

Public exploit code is referenced for this CVE (1 GitHub PoC). Defenders should treat patch urgency accordingly.

  • GitHub PoCc0r0n3r/dheater
    Published Aug 31, 2021

    D(HE)ater is a proof of concept implementation of the D(HE)at attack (CVE-2002-20001) through which denial-of-service can be performed by enforcing the Diffie-Hellman key exchange. (read-only clone of the original GitLab project)

    Open source ↗

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2002-20001?
CVE-2002-20001 is a high vulnerability published on November 11, 2021. 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…
When was the CVE record for CVE-2002-20001 published?
The CVE record for CVE-2002-20001 was published on November 11, 2021. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of September 23, 2026; the record at its source may have been updated since.
Is CVE-2002-20001 actively exploited?
CVE-2002-20001 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 25% probability of exploitation in the next 30 days (97th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2002-20001?
CVE-2002-20001 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2002-20001?
No fix for CVE-2002-20001 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2002-20001

Explore →

Is Your Infrastructure Affected by CVE-2002-20001?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Book a Demo →Browse All CVEs