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CVE-2016-4503: Moxa Device Server Web Console 5232 N Firmware: Authentication bypass

CVE-2016-4503 is rated critical with a CVSS v3.1 base score of 9.8 and NVD lists Moxa Device Server Web Console 5232 N Firmware as the affected product. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

Moxa Device Server Web Console 5232-N allows remote attackers to bypass authentication, and consequently modify settings and data, via vectors related to reading a cookie parameter containing a UserId value.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-287: Improper Authentication

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

Affected products

  • Moxa Device Server Web Console 5232 N Firmware: all versions listed by NVD

References