Erlang/OTP SSH Flaw Alert

Security teams have identified a maximum-severity vulnerability-CVE-2025-32433-in the SSH implementation of Erlang/OTP, a platform widely deployed in telecom, industrial control systems (ICS), IoT devices, and other high-availability environments. The flaw enables unauthenticated remote code execution, allowing attackers to run arbitrary commands before authentication completes.

Why It Matters
  • Wide Reach: The issue affects any application using the OTP SSH server-including critical systems from Cisco, Ericsson, and others.
  • Real-World Exploitation: Since May 2025, attackers have begun exploiting the flaw, particularly targeting OT firewall systems. CISA has officially added it to its Known Exploited Vulnerabilities (KEV) catalog.
  • Simple Exploitability: Proof-of-concept code is now public, making it easier for attackers to compromise systems.
  • Potential Impact: Once exploited, devices can be fully controlled by malicious actors, risking ransomware deployment, data theft, or operational disruption.
Security Actions Required

To mitigate this urgent threat:

  • Apply vendor-released patches for OTP versions 27.3.3, 26.2.5.11, or 25.3.2.20.
  • Restrict access to Erlang-based SSH services with firewall rules and IP whitelisting.
  • Disable the SSH module on Erlang applications if unnecessary.([turn0search7])
  • Monitor for unexpected connections and pre-auth interactions via EDR or SIEM platforms.
  • Validate vendor readiness-many third-party devices ship with embedded Erlang that needs patching.
Industries Most At Risk

This vulnerability poses a serious risk to sectors including:

  • Telecommunications and Network Infrastructure due to embedded Erlang software.
  • Industrial and Critical Infrastructure (Energy, Utilities, Manufacturing) where OT systems rely on Erlang communication.
  • Telecom Equipment Providers and IoT Deployments vulnerable to invisible escalation and payload delivery.
Conclusion

CVE-2025-32433 highlights the hidden risks in trusted system components within critical infrastructure. Rapid patching, architecture review, and robust monitoring are essential-not optional-for uninterrupted, secure operations.

About COE Security

COE Security partners with organizations in financial services, healthcare, retail, manufacturing, and government to secure AI-powered systems and ensure compliance. Our offerings include:

  • AI-enhanced threat detection and real-time monitoring
  • Data governance aligned with GDPR, HIPAA, and PCI DSS
  • Secure model validation to guard against adversarial attacks
  • Customized training to embed AI security best practices
  • Penetration Testing (Mobile, Web, AI, Product, IoT, Network & Cloud)
  • Secure Software Development Consulting (SSDLC)
  • Customized CyberSecurity Services

Additionally, we help organizations in sectors like telecom, industrial automation, and IoT secure their infrastructure against systemic vulnerabilities. We provide architecture audits, patch prioritization strategies, and real-time monitoring tailored to environments with embedded Erlang components.

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