NEC EXPRESSCLUSTER X Disk Agent 0x103 Stack Overflow Vulnerability


A stack-based buffer overflow has been found in NEC EXPRESSCLUSTER X that can lead to remote arbitrary code execution with full SYSTEM privileges. The Disk Agent (clpdiskagent.exe) is the component that is tasked with handling shared disk resources and mirror disk control. It is configured to utilize port 29004 by default to facilitate communications between agents. This vulnerability occurs during the processing of opcode 0x103 when initializing a CPROGAGT routine within the Disk Agent. An attacker is able to introduce crafted data into the clpdiskagent component to allow for arbitrary code execution.

Vulnerability Identifiers

  • Exodus Intelligence: EIP-ff1ca610
  • MITRE CVE: CVE-2021-20700

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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