CVE intelligence and bounded remediation

CVE-2020-24686 — Abb Pm554 Firmware security vulnerability

High CVSS 7.5

The vulnerabilities can be exploited to cause the web visualization component of the PLC to stop and not respond, leading to genuine users losing remote visibility of the PLC state. If a user attempts to login to the PLC while this vulnerability is exploited, the PLC will show an error state and refuse connections to Automation Builder. The execution of the PLC application is not affected by this vulnerability. This issue affects ABB AC500 V2 products with onboard Ethernet.

Severity
High
CVSS
7.5 (3.1)
Published
2021-02-26
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-400

Affected products

  • abb / pm554_firmware
  • abb / pm556_firmware
  • abb / pm564_firmware
  • abb / pm566_firmware
  • abb / pm572_firmware
  • abb / pm573_firmware

Matched remediation archetype

Resource exhaustion and denial of service

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.