CVE-2020-22218 ABB CVE debrief

Who should care

Operators, integrators, and defenders responsible for ABB M2M Gateway ARM600 deployments, especially OT environments using affected firmware/software ranges. Security teams should care if the gateway is reachable from untrusted networks or used in remote-access paths.

Technical summary

The advisory identifies a memory-safety flaw in libssh2’s _libssh2_packet_add path, described as allowing access to out-of-bounds memory. The supplied CVSS vector (AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H) indicates a network-reachable issue requiring low privileges and no user interaction, with availability impact as the main consequence. CISA’s CSAF scope lists ABB M2M Gateway ARM600 firmware versions 4.1.2 through 5.0.3 and ABB M2M Gateway SW versions 5.0.1 through 5.0.3 as affected.

Defensive priority

Medium

Recommended defensive actions

• Determine whether any ABB M2M Gateway ARM600 firmware or ABB M2M Gateway SW deployment falls within the affected version ranges listed in the advisory.
• Review ABB and CISA guidance for the product and move affected systems away from exposed configurations where possible.
• Avoid exposing ARM600 components directly to the internet; if internet connectivity is required, expose only the necessary VPN port.
• Use a private cellular APN or other segregated WAN option when available so remote traffic does not traverse the public internet.
• Apply the allowlisting principle on firewalls and allow only required ports, protocols, source hosts, and destination hosts.
• If the internet is used as WAN transport, terminate traffic in a DMZ and segregate the ARM600 from other networks with a firewall.
• Change default credentials, use unique strong passwords, and restrict administrator/root use to tasks that require it.
• Keep supporting engineering or configuration PCs updated, scan transferred files for malware, and maintain validated backups of configurations and firmware files.

Evidence notes

The source corpus is a CISA CSAF advisory (ICSA-25-105-08) published 2025-04-07 and mapped to ABB M2M Gateway ARM600 / ABB M2M Gateway SW. It explicitly states the vulnerable function is _libssh2_packet_add in libssh2, that attackers may access out-of-bounds memory, and that the issue could lead to a system crash by an authenticated attacker. The advisory’s affected-product entries list ARM600 firmware 4.1.2 through 5.0.3 and SW 5.0.1 through 5.0.3. No KEV listing is present in the supplied enrichment.

Official resources