Pepperl+Fuchs ICE2 — Schwachstelle 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.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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.