CyberSecBulletin
CVE-2023-43742NVD status: Modified

Mx-se Firmware: Improper Authentication

Published Updated By the CyberSecBulletin desk

CVE-2023-43742 is a critical-severity improper authentication vulnerability in Mx-se Firmware from Zultys, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 16.0.4, 17.0.10 as the first without the flaw, so updating Mx-se Firmware to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.92% chance of exploitation within 30 days, higher than 61% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update Mx-se Firmware to 16.0.4 or 17.0.10, whichever matches your release line, or a later version.
  2. Update Mx-se Ii Firmware to 16.0.4 or 17.0.10, whichever matches your release line, or a later version.
  3. Update Mx-e Firmware to 16.0.4 or 17.0.10, whichever matches your release line, or a later version.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
ZultysMx-se Firmwarebefore 16.0.4; 17.0.6 up to, but not including, 17.0.1016.0.4, 17.0.10
ZultysMx-se Ii Firmwarebefore 16.0.4; 17.0.6 up to, but not including, 17.0.1016.0.4, 17.0.10
ZultysMx-e Firmwarebefore 16.0.4; 17.0.6 up to, but not including, 17.0.1016.0.4, 17.0.10
ZultysMx-virtual Firmwarebefore 16.0.4; 17.0.6 up to, but not including, 17.0.1016.0.4, 17.0.10
ZultysMx250 Firmwarebefore 16.0.4; 17.0.6 up to, but not including, 17.0.1016.0.4, 17.0.10
ZultysMx30 Firmwarebefore 16.0.4; 17.0.6 up to, but not including, 17.0.1016.0.4, 17.0.10

Version data comes from NVD's product matching. 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
NoneNo account or login is needed.
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:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Official description

An authentication bypass in Zultys MX-SE, MX-SE II, MX-E, MX-Virtual, MX250, and MX30 with firmware versions prior to 17.0.10 patch 17161 and 16.04 patch 16109 allows an unauthenticated attacker to obtain an administrative session via a protection mechanism failure in the authentication function. In normal operation, the Zultys MX Administrator Windows client connects to port 7505 and attempts authentication, submitting the administrator username and password to the server. Upon authentication failure, the server sends a login failure message prompting the client to disconnect. However, if the client ignores the failure message instead and attempts to continue, the server does not forcibly close the connection and processes all subsequent requests from the client as if authentication had been successful.

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

The underlying weakness: Improper Authentication

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

How developers prevent this class of flaw

  • Use an authentication framework or library such as the OWASP ESAPI Authentication feature.

More Improper Authentication vulnerabilities (CWE-287)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Mx-se Firmware

All Mx-se Firmware vulnerabilities

Recent Improper Authentication vulnerabilities

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