Loading vulnerabilities…
Loading vulnerabilities…
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.
This record: live connection— last retrieved: 7 November 2026 at 02:35.
Vendor
Published
11 November 2021
Last modified
23 September 2026
Taken directly from NVD, CISA or the vendor — sometimes in English, unchanged from the source.
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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
NETWORK
Privileges required
NONE
User interaction
NONE
Confidentiality
None
Integrity
None
Availability
High
Probability of exploitation within 30 days
24.6%
Percentile
98e
Source: FIRST.org, updated on 6 November 2026.
External protective measures are required: Disable the webserver after configuration, if possible, by following these steps: - Enable SSH via the web server. - Login to the SSH server. - Disable the webserver via SSH portal. - Reboot the device. or: - Use HTTPS rather than HTTP while using the webserver. - Minimize network exposure for affected products and ensure that they are not accessible via the Internet. - Isolate affected products from the corporate network. - If remote access is required, use secure methods such as virtual private networks(VPNs). Pepperl+Fuchs will provide an update to address some of these vulnerabilities in the future.
Our own interpretation and context for the source data above.
IACS Radar assessment
Our own interpretation and context for this vulnerability — not an official source.
IACS Radar priority score
Based on CVSS 7.5, EPSS 24.6%, industrial relevance 40/100.
Combines CVSS, EPSS, KEV status, industrial relevance and exposure relevance — a complement to, not a replacement for, the individual scores below and above.
Conditions for exploitation
Operational impact & energy relevance
Possible loss of visibility of or control over the process upon successful exploitation.
No strong energy-sector-specific signals recognised; general OT/ICS relevance.
Recommended defensive measures
Industrial relevance score
Classification is provisional; manual verification by an OT security analyst is recommended.
Classified by IACS Radar-analysepijplijn (geautomatiseerd) on 7 November 2026.
IEC 62443 mapping
Automatic IACS Radar assessment based on the reported CWE weakness classification; not an official certification statement.