HIGH
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
Published Nov 11, 2021
7.5
HIGHCVSS 3.1
EPSS 24.64%
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.
Affected products
No data.
Configuration 2
AND
- n/a
Running on/with
- n/a
Configuration 3
OR
- 11
- 12
- 15
Configuration 4
OR
- ≥ 13.1.0 · < 16.1.4
- ≥ 17.0.0 · < 17.1.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- 1.6.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 13.1.0 · ≤ 17.1.2
- 17.5.0
- ≥ 8.0.0 · ≤ 8.4.0
- 7.1.0
- 5.1.0
- 5.2.0
- ≥ 1.3.0 · ≤ 1.3.2
- ≥ 1.5.0 · ≤ 1.5.3
- 1.8.0
- ≥ 1.3.0 · ≤ 1.3.2
- ≥ 1.6.0 · ≤ 1.6.2
- 1.5.0
- 1.5.1
- 1.8.0
- 1.8.1
Configuration 5
AND
OR
- ≥ 10.06.0000 · < 10.06.0180
- ≥ 10.07.0000 · < 10.07.0030
- ≥ 10.08.0000 · < 10.08.0010
- ≥ 10.09.0000 · < 10.09.0002
Running on/with
OR
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
Configuration 6
OR
- < 3.3.3
- ≥ 2.7.0 · < 4.3.16
- ≥ 4.4.0 · < 4.6.3
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
7.5 HIGH NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact None
Availability Impact High
No CVSS v3.0 score for this CVE.
5.0 MEDIUM NVD
AV:N/AC:L/Au:N/C:N/I:N/A:P
Access Vector Network
Access Complexity Low
Authentication None
Confidentiality Impact None
Integrity Impact None
Availability Impact Partial
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
24.64% 0.24639
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
EPSS probability 0.24639
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (79 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 24.64% (0.24639) | 97.82th | v5 (v2026.06.15) |
| Sep 4, 2026 | 24.64% (0.24639) | 97.73th | v5 (v2026.06.15) |
| Jun 15, 2026 | 23.06% (0.23061) | 97.46th | v5 (v2026.06.15) |
| Jun 7, 2026 | 18.72% (0.18716) | 95.42th | v4 (v2025.03.14) |
| Mar 4, 2026 | 14.68% (0.14680) | 94.34th | v4 (v2025.03.14) |
| Mar 1, 2026 | 13.45% (0.13451) | 94.09th | v4 (v2025.03.14) |
| Feb 4, 2026 | 14.68% (0.14680) | 94.30th | v4 (v2025.03.14) |
| Feb 1, 2026 | 13.45% (0.13451) | 94.05th | v4 (v2025.03.14) |
| Jan 23, 2026 | 14.68% (0.14680) | 94.28th | v4 (v2025.03.14) |
| Jan 18, 2026 | 11.63% (0.11632) | 93.44th | v4 (v2025.03.14) |
| Jan 4, 2026 | 14.68% (0.14680) | 94.26th | v4 (v2025.03.14) |
| Jan 1, 2026 | 13.45% (0.13451) | 94.02th | v4 (v2025.03.14) |
| Dec 30, 2025 | 14.68% (0.14680) | 94.26th | v4 (v2025.03.14) |
| Dec 18, 2025 | 11.63% (0.11632) | 93.41th | v4 (v2025.03.14) |
| Dec 4, 2025 | 14.68% (0.14680) | 94.21th | v4 (v2025.03.14) |
| Dec 1, 2025 | 13.45% (0.13451) | 93.97th | v4 (v2025.03.14) |
| Nov 4, 2025 | 14.68% (0.14680) | 94.19th | v4 (v2025.03.14) |
| Nov 3, 2025 | 13.45% (0.13451) | 93.94th | v4 (v2025.03.14) |
| Nov 1, 2025 | 10.62% (0.10618) | 92.98th | v4 (v2025.03.14) |
| Oct 21, 2025 | 11.63% (0.11632) | 93.32th | v4 (v2025.03.14) |
| Oct 4, 2025 | 14.68% (0.14680) | 94.24th | v4 (v2025.03.14) |
| Oct 1, 2025 | 13.45% (0.13451) | 93.99th | v4 (v2025.03.14) |
| Sep 18, 2025 | 11.63% (0.11632) | 93.41th | v4 (v2025.03.14) |
| Sep 4, 2025 | 14.68% (0.14680) | 94.24th | v4 (v2025.03.14) |
| Sep 1, 2025 | 13.45% (0.13451) | 93.98th | v4 (v2025.03.14) |
| Aug 28, 2025 | 14.68% (0.14680) | 94.22th | v4 (v2025.03.14) |
| Aug 16, 2025 | 11.63% (0.11632) | 93.38th | v4 (v2025.03.14) |
| Aug 5, 2025 | 14.68% (0.14680) | 94.19th | v4 (v2025.03.14) |
| Aug 1, 2025 | 13.45% (0.13451) | 93.95th | v4 (v2025.03.14) |
| Jul 4, 2025 | 14.68% (0.14680) | 94.16th | v4 (v2025.03.14) |
| Jul 1, 2025 | 13.45% (0.13451) | 93.91th | v4 (v2025.03.14) |
| Jun 24, 2025 | 14.68% (0.14680) | 94.14th | v4 (v2025.03.14) |
| Jun 15, 2025 | 11.63% (0.11632) | 93.29th | v4 (v2025.03.14) |
| Jun 5, 2025 | 14.68% (0.14680) | 94.12th | v4 (v2025.03.14) |
| Jun 3, 2025 | 13.45% (0.13451) | 93.85th | v4 (v2025.03.14) |
| Jun 1, 2025 | 10.62% (0.10618) | 92.92th | v4 (v2025.03.14) |
| May 21, 2025 | 11.63% (0.11632) | 93.28th | v4 (v2025.03.14) |
| May 16, 2025 | 14.68% (0.14680) | 94.10th | v4 (v2025.03.14) |
| May 15, 2025 | 18.72% (0.18716) | 94.91th | v4 (v2025.03.14) |
| May 6, 2025 | 5.34% (0.05344) | 89.50th | v4 (v2025.03.14) |
| May 4, 2025 | 4.01% (0.04007) | 87.80th | v4 (v2025.03.14) |
| May 1, 2025 | 1.98% (0.01980) | 82.63th | v4 (v2025.03.14) |
| Apr 20, 2025 | 4.01% (0.04007) | 87.81th | v4 (v2025.03.14) |
| Apr 19, 2025 | 1.98% (0.01980) | 82.56th | v4 (v2025.03.14) |
| Apr 16, 2025 | 4.01% (0.04007) | 87.78th | v4 (v2025.03.14) |
| Apr 15, 2025 | 1.98% (0.01980) | 82.49th | v4 (v2025.03.14) |
| Apr 14, 2025 | 4.01% (0.04007) | 87.44th | v4 (v2025.03.14) |
| Apr 13, 2025 | 1.98% (0.01980) | 82.07th | v4 (v2025.03.14) |
| Apr 2, 2025 | 4.01% (0.04007) | 87.41th | v4 (v2025.03.14) |
| Apr 1, 2025 | 2.15% (0.02154) | 82.78th | v4 (v2025.03.14) |
| Mar 30, 2025 | 4.55% (0.04553) | 88.15th | v4 (v2025.03.14) |
| Mar 29, 2025 | 14.99% (0.14994) | 90.96th | v4 (v2025.03.14) |
| Mar 28, 2025 | 4.55% (0.04553) | 88.17th | v4 (v2025.03.14) |
| Mar 27, 2025 | 14.99% (0.14994) | 93.63th | v4 (v2025.03.14) |
| Mar 26, 2025 | 4.55% (0.04553) | 88.06th | v4 (v2025.03.14) |
| Mar 25, 2025 | 2.26% (0.02259) | 83.03th | v4 (v2025.03.14) |
| Mar 22, 2025 | 4.55% (0.04553) | 88.24th | v4 (v2025.03.14) |
| Mar 20, 2025 | 2.26% (0.02259) | 83.19th | v4 (v2025.03.14) |
| Mar 19, 2025 | 13.97% (0.13972) | 93.50th | v4 (v2025.03.14) |
| Mar 18, 2025 | 4.20% (0.04197) | 88.02th | v4 (v2025.03.14) |
| Mar 17, 2025 | 1.56% (0.01557) | 80.19th | v4 (v2025.03.14) |
| Feb 12, 2025 | 2.56% (0.02564) | 90.07th | v3 (v2023.03.01) |
| Dec 12, 2024 | 1.17% (0.01166) | 85.58th | v3 (v2023.03.01) |
| Jun 17, 2024 | 1.07% (0.01074) | 84.30th | v3 (v2023.03.01) |
| Apr 23, 2024 | 1.05% (0.01046) | 83.81th | v3 (v2023.03.01) |
| Feb 3, 2024 | 1.00% (0.01004) | 82.08th | v3 (v2023.03.01) |
| Jan 17, 2024 | 0.78% (0.00778) | 79.43th | v3 (v2023.03.01) |
| Jul 8, 2023 | 0.54% (0.00544) | 74.27th | v3 (v2023.03.01) |
| Jul 3, 2023 | 0.70% (0.00703) | 77.62th | v3 (v2023.03.01) |
| Jun 19, 2023 | 0.72% (0.00719) | 77.89th | v3 (v2023.03.01) |
| Jun 4, 2023 | 0.73% (0.00728) | 78.01th | v3 (v2023.03.01) |
| May 17, 2023 | 0.75% (0.00746) | 78.25th | v3 (v2023.03.01) |
| Apr 24, 2023 | 2.28% (0.02277) | 88.00th | v3 (v2023.03.01) |
| Mar 15, 2023 | 1.90% (0.01898) | 86.68th | v3 (v2023.03.01) |
| Mar 7, 2023 | 1.35% (0.01346) | 84.03th | v3 (v2023.03.01) |
| Mar 6, 2023 | 26.13% (0.26127) | 97.09th | v2 (v2022.01.01) |
| Nov 9, 2022 | 26.13% (0.26127) | 96.99th | v2 (v2022.01.01) |
| Apr 1, 2022 | 7.18% (0.07176) | 91.55th | v2 (v2022.01.01) |
| Feb 4, 2022 | 7.18% (0.07176) | 80.33th | v2 (v2022.01.01) |
Weaknesses (1)
References (13)
- https://cert-portal.siemens.com/productcert/pdf/ssa-506569.pdf Third Party Advisory
- https://dheatattack.com Third Party Advisory
- https://dheatattack.gitlab.io/ Third Party Advisory
- https://github.com/Balasys/dheater ProductThird Party Advisory
- https://github.com/mozilla/ssl-config-generator/issues/162 Issue Tracking
- https://gitlab.com/dheatattack/dheater Third Party Advisory
- https://ieeexplore.ieee.org/document/10374117 Technical DescriptionThird Party Advisory
- https://support.f5.com/csp/article/K83120834 Third Party Advisory
- https://www.arubanetworks.com/assets/alert/ARUBA-PSA-2022-004.txt Technical DescriptionThird Party Advisory
- https://www.openssl.org/blog/blog/2022/10/21/tls-groups-configuration/ Third Party Advisory
- https://www.reddit.com/r/netsec/comments/qdoosy/server_overload_by_enforcing_dhe_key_exchange/ Issue Tracking
- https://www.researchgate.net/profile/Anton-Stiglic-2/publication/2401745_Security_Issues_in_the_Diffie-Hellman_Key_Agreement_Protocol ExploitTechnical Description
- https://www.suse.com/support/kb/doc/?id=000020510 Third Party Advisory
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner mitre
Published Nov 11, 2021
Updated Feb 13, 2025
Reserved Nov 11, 2021
Link CVE-2002-20001
CISA Vulnrichment
Updated n/a