ZyXEL Armor Cross-Site Request Forgery Vulnerability


A cross-site request forgery vulnerability exists within the ZyXEL Armor Z1 AC2350 and Z2 AC2600 series. Exploitation of the vulnerability allows for attackers to run arbitrary commands on vulnerable versions of the firmware under the context of the root user. Exploitation requires either that the attacker has access to the local network or is able to coerce a local user into visiting a malicious website.

Vulnerability Identifiers

  • Exodus Intelligence: EIP-521a3b40
  • MITRE CVE: CVE-2021-4030

Vulnerability Metrics

  • CVSSv2 Score: 7.9

Vendor References

  • https://www.zyxel.com/support/forgery-vulnerabilities-of-select-Armor-home-routers.shtml

Discovery Credit

  • Exodus Intelligence

Disclosure Timeline

  • Disclosed to affected vendor: December 14th, 2021
  • Disclosed to public: February 22nd, 2022

Further Information

Readers of this advisory who are interested in receiving further details around the vulnerability, mitigations, detection guidance, and more can contact us at sales@exodusintel.com.

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