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CVE-2017-7909: Advantech B+B Smartworx Mesr901 Firmware: Authentication bypass

CVE-2017-7909 is rated critical with a CVSS v3.0 base score of 9.8 and affects Advantech B+B Smartworx Mesr901 Firmware. 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

A Use of Client-Side Authentication issue was discovered in Advantech B+B SmartWorx MESR901 firmware versions 1.5.2 and prior. The web interface uses JavaScript to check client authentication and redirect unauthorized users. Attackers may intercept requests and bypass authentication to access restricted web pages.

Severity breakdown

CVSS v3.0 9.8: CVSS:3.0/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-603: Use of Client-Side Authentication

A client/server product performs authentication within client code but not in server code, allowing server-side authentication to be bypassed via a modified client that omits the authentication check.

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

  • Advantech B+B Smartworx Mesr901 Firmware: up to and including 1.5.2

References