NEC EXPRESSCLUSTER X Transaction Server 0x3A 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 Transaction Server (clptrnsv.exe) is a system service configured to utilize port 29002 by default to facilitate transactions such as sending and receiving licensing data. This vulnerability occurs during the processing of opcode 0x3A when initializing a clpexescript routine within the Transaction Server. An attacker is able to introduce crafted data into the clptrnsv service to allow for arbitrary code execution.

Vulnerability Identifiers

  • Exodus Intelligence: EIP-fba18752
  • MITRE CVE: CVE-2021-20702

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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