Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2023-39547 is a high-severity Authentication Bypass by Capture-replay (CWE-294) vulnerability in Nec Expresscluster X. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Protocol or Service Impersonation (T1001.003); ranked at the 49th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-43257
Vulnerability Data
CLUSTERPRO X Ver5.1 and earlier and EXPRESSCLUSTER X 5.1 and earlier, CLUSTERPRO X SingleServerSafe 5.1 and earlier, EXPRESSCLUSTER X SingleServerSafe 5.1 and earlier allows a attacker to log in to the product may execute an arbitrary command.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V10.4.16V10.5.1
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Allows detection of capture-replay attacks by showing the replayed logon's timestamp as the last logon.
Protects against replay of captured session tokens or credentials by requiring authenticated, fresh session channels.
Wireless link protections commonly incorporate replay protection, reducing the exploitability of capture-replay weaknesses.
Accurate synchronized time enables tight timestamp windows that directly limit capture-replay windows in authentication protocols.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Network monitoring may detect anomalous replays after the fact but does not prevent the design flaw.
Strong authentication methods can reduce replay risk but do not inherently address captured messages.
Protecting and verifying identity assertions prevents replay of captured authentication material.
Encryption and integrity protections for data-in-transit directly block capture-replay of credentials or tokens.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.