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CVE-2019-16920: D-Link Multiple Routers Command Injection Vulnerability

CVE-2019-16920 is rated critical with a CVSS v3.1 base score of 9.8 and affects D-Link Multiple Routers, along with 10 other products in NVD’s configuration data. 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. CISA added it to its Known Exploited Vulnerabilities catalog on 2022-03-25, which means exploitation in the wild has been observed.

Vulnerability description

Unauthenticated remote code execution occurs in D-Link products such as DIR-655C, DIR-866L, DIR-652, and DHP-1565. The issue occurs when the attacker sends an arbitrary input to a "PingTest" device common gateway interface that could lead to common injection. An attacker who successfully triggers the command injection could achieve full system compromise. Later, it was independently found that these are also affected: DIR-855L, DAP-1533, DIR-862L, DIR-615, DIR-835, and DIR-825.

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-78: Improper Neutralization of Special Elements used in an OS Command

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.

Affected products

  • D-Link Dir 655 Firmware: up to and including 3.02b05
  • D-Link Dir 866l Firmware: up to and including 1.03b04
  • D-Link Dir 652 Firmware: all versions listed by NVD
  • D-Link Dhp 1565 Firmware: up to and including 1.01
  • D-Link Dir 855l Firmware: all versions listed by NVD
  • D-Link Dap 1533 Firmware: all versions listed by NVD
  • D-Link Dir 862l Firmware: all versions listed by NVD
  • D-Link Dir 615 Firmware: all versions listed by NVD
  • D-Link Dir 835 Firmware: all versions listed by NVD
  • D-Link Dir 825 Firmware: all versions listed by NVD

References