Command Injection (CVE‑2018‑14558) in Tenda AC7/AC9/AC10 Routers Allows Remote OS Command Execution
What It Is – The “formsetUsbUnload” handler in Tenda AC7, AC9 and AC10 Wi‑Fi routers passes unchecked user input to a system‑level command (dosystemCmd). An attacker can craft a goform/setUsbUnload request that injects arbitrary OS commands.
Exploitability – The flaw is remotely exploitable over HTTP with no authentication required. Public PoCs exist; the vendor has released a firmware patch. CVSS v3.1 base score is 7.8 (High).
Affected Products – Tenda AC7, AC9 and AC10 wireless routers (various hardware revisions).
Why It Matters for Trust & Control Assurance
- Demonstrates the need for continuous vulnerability‑management evidence: without timely patching, the control “Maintain secure configuration” is broken, exposing the organization to audit findings across SOC 2, ISO 27001, NIST CSF, etc.
- Highlights gaps in network‑device logging and monitoring; an exploited router can become a foothold for lateral movement, undermining the audit trail required for defensible evidence.
- Forces organizations to prove supply‑chain diligence—the ability to verify that third‑party hardware is kept up‑to‑date is a core control objective that satisfies many frameworks simultaneously.
Recommended Actions
- Inventory all Tenda AC7/AC9/AC10 devices and verify firmware version.
- Apply the vendor‑supplied firmware update (or replace devices that cannot be patched).
- Segment consumer‑grade routers from critical internal networks and enforce strict ACLs.
- Enable and centralize syslog output from the routers; monitor for anomalous command‑execution patterns.
- Incorporate the router patch status into your continuous control‑mapping dashboard to retain audit‑ready evidence.
Source: CISA KEV – CVE‑2018‑14558