CVE intelligence and bounded remediation

CVE-2020-12834 — Eq-3 Homematic Ccu2 Firmware security vulnerability

Critical CVSS 9.8

eQ-3 Homematic Central Control Unit (CCU)2 through 2.51.6 and CCU3 through 3.51.6 allow Remote Code Execution in the JSON API Method ReGa.runScript, by unauthenticated attackers with access to the web interface, due to the default auto-login feature being enabled during first-time setup (or factory reset).

Severity
Critical
CVSS
9.8 (3.1)
Published
2020-05-15
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-276

Affected products

  • eq-3 / homematic_ccu2_firmware
  • eq-3 / ccu3_firmware

Matched remediation archetype

Privilege escalation and unsafe privilege management

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

Check exposure

  • Map service accounts, operating-system identities, roles, capabilities, impersonation, set-user transitions, and administrative helper paths.
  • Determine whether untrusted users or lower-privilege processes can reach the affected transition or modify inputs it trusts.
  • Review file, socket, registry, device, job, container, and cloud-role permissions used before and after privilege changes.

Remediate safely

  • Apply the supported fix and redesign privileged operations as a minimal, authenticated, allowlisted interface.
  • Drop privileges before processing untrusted input, verify the drop succeeds, and remove unnecessary roles, capabilities, and write permissions.
  • Validate ownership and permissions at time of use and add explicit lower-to-higher privilege boundary tests.

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.