NEC EXPRESSCLUSTER X Web Manager File Upload Vulnerability


An arbitrary file upload vulnerability has been found in NEC EXPRESSCLUSTER X. WebManager (clpwebmc.exe) is a webserver tasked with providing remote administrative access, it is configured to utilize port 29003 by default. This vulnerability occurs due to lack of input validation when supplying “UploadFile.js”. An attacker is able to transmit binary data resulting in eventual remote code execution in the context of SYSTEM.

Vulnerability Identifiers

  • Exodus Intelligence: EIP-d8554689
  • MITRE CVE: CVE-2021-20705

Vulnerability Metrics

  • CVSSv2 Score: 10.0

Vendor References

Discovery Credit

  • Exodus Intelligence

Disclosure Timeline

  • Disclosed to affected vendor: February 25th, 2021
  • Disclosed to public: October 29th, 2021

Further Information

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