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Vulnerability record · CVE-2021-20702 · published 3 November 2021

CVE-2021-20702: Nec clusterpro x classic buffer overflow vulnerability

Nec · Clusterpro X

Buffer overflow vulnerability in the Transaction Server CLUSTERPRO X 4.3 for Windows and earlier, EXPRESSCLUSTER X 4.3 for Windows and earlier, CLUSTERPRO X 4.3 SingleServerSafe for Windows and earlier, EXPRESSCLUSTER X 4.3 SingleServerSafe for Windows and earlier allows attacker to remote code execution via a network.

9.8 CVSS 3.1 Critical EPSS 2.2% · top 18.2% CWE-120 · Classic buffer overflow
9.8CVSS 3.1 base score, v2 7.5
2.2%EPSS exploitation probability, 30 days
NoNot in CISA KEV
4Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

Buffer overflow vulnerability in the Transaction Server CLUSTERPRO X 4.3 for Windows and earlier, EXPRESSCLUSTER X 4.3 for Windows and earlier, CLUSTERPRO X 4.3 SingleServerSafe for Windows and earlier, EXPRESSCLUSTER X 4.3 SingleServerSafe for Windows and earlier allows attacker to remote code execution via a network.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

4 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://jpn.nec.com/security-info/secinfo/nv21-015_en.html
https://jpn.nec.com/security-info/secinfo/nv21-015_en.html

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2022-34824Nec expresscluster x incorrect default permissions vulnerabilityWeak File and Folder Permissions vulnerability in CLUSTERPRO X 5.0 for Windows and earlier, EXPRESSCLUSTER X 5.0 for Windows and earlier, CLUSTERPRO …EPSS 1.2%9.8CVE-2022-34825Nec expresscluster x uncontrolled search path element vulnerabilityUncontrolled Search Path Element in CLUSTERPRO X 5.0 for Windows and earlier, EXPRESSCLUSTER X 5.0 for Windows and earlier, CLUSTERPRO X 5.0 SingleSe…EPSS 1.3%9.8CVE-2022-34822Nec expresscluster x path traversal vulnerabilityPath traversal vulnerability in CLUSTERPRO X 5.0 for Windows and earlier, EXPRESSCLUSTER X 5.0 for Windows and earlier, CLUSTERPRO X 5.0 SingleServer…EPSS 1.5%9.8CVE-2022-34823Nec expresscluster x classic buffer overflow vulnerabilityBuffer overflow vulnerability in CLUSTERPRO X 5.0 for Windows and earlier, EXPRESSCLUSTER X 5.0 for Windows and earlier, CLUSTERPRO X 5.0 SingleServe…EPSS 1.4%9.8CVE-2021-20700Nec clusterpro x classic buffer overflow vulnerabilityBuffer overflow vulnerability in the Disk Agent CLUSTERPRO X 4.3 for Windows and earlier, EXPRESSCLUSTER X 4.3 for Windows and earlier, CLUSTERPRO X …EPSS 2.1%9.8CVE-2021-20701Nec clusterpro x classic buffer overflow vulnerabilityBuffer overflow vulnerability in the Disk Agent CLUSTERPRO X 4.3 for Windows and earlier, EXPRESSCLUSTER X 4.3 for Windows and earlier, CLUSTERPRO X …EPSS 2.1%9.8CVE-2021-20703Nec clusterpro x classic buffer overflow vulnerabilityBuffer overflow vulnerability in the Transaction Server CLUSTERPRO X 4.3 for Windows and earlier, EXPRESSCLUSTER X 4.3 for Windows and earlier, CLUST…EPSS 2.1%9.8CVE-2021-20704Nec clusterpro x classic buffer overflow vulnerabilityBuffer overflow vulnerability in the compatible API with previous versions CLUSTERPRO X 4.3 for Windows and earlier, EXPRESSCLUSTER X 4.3 for Windows…EPSS 2.1%

Source: NIST National Vulnerability Database (record CVE-2021-20702), CISA KEV, FIRST EPSS (scores of 2026-09-29). This page is refreshed as NVD updates the record.