CyberSecBulletin
CVE-2023-39547NVD status: Modified

CLUSTERPRO X (EXPRESSCLUSTER X): Authentication Bypass by Capture-replay

Published Updated By the CyberSecBulletin desk

CVE-2023-39547 is a high-severity authentication bypass by capture-replay vulnerability in CLUSTERPRO X (EXPRESSCLUSTER X) from NEC, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected CLUSTERPRO X (EXPRESSCLUSTER X) versions: 1.0, 2.0 2.1, 3.0, 3.1, 3.2, 4.0, 4.1, 4.2, 5.0 and 5.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.63% chance of exploitation within 30 days, higher than 51% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of CLUSTERPRO X (EXPRESSCLUSTER X) you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
NECCLUSTERPRO X (EXPRESSCLUSTER X)1.0, 2.0 2.1, 3.0, 3.1, 3.2, 4.0, 4.1, 4.2, 5.0 and 5.1Not stated
NECCLUSTERPRO X SingleServerSafe (EXPRESSCLUSTER X SingleServerSafe)1.0, 2.0 2.1, 3.0, 3.1, 3.2, 4.0, 4.1, 4.2, 5.0 and 5.1Not stated
NecExpresscluster X1.0; 2.0; 2.1; 3.0; 3.1; 3.2; 3.3; 4.0; and 4 more rangesNot stated
NecExpresscluster X Singleserversafe1.0; 2.0; 2.1; 3.0; 3.1; 3.2; 3.3; 4.0; and 4 more rangesNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Official description

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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Authentication Bypass by Capture-replay

A capture-replay flaw exists when the design of the product makes it possible for a malicious user to sniff network traffic and bypass authentication by replaying it to the server in question to the same effect as the original message (or with minor changes).

How developers prevent this class of flaw

  • Utilize some sequence or time stamping functionality along with a checksum which takes this into account in order to ensure that messages can be parsed only once.
  • Since any attacker who can listen to traffic can see sequence numbers, it is necessary to sign messages with some kind of cryptography to ensure that sequence numbers are not simply doctored along with content.

More Authentication Bypass by Capture-replay vulnerabilities (CWE-294)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Other vulnerabilities in CLUSTERPRO X (EXPRESSCLUSTER X)

All CLUSTERPRO X (EXPRESSCLUSTER X) vulnerabilities

Recent Authentication Bypass by Capture-replay vulnerabilities

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