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CVE-2018-20114: D-Link Dir 818lw Firmware: Authentication bypass
CVE-2018-20114 is rated critical with a CVSS v3.1 base score of 9.8 and NVD lists 2 affected products, including D-Link Dir 818lw 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
On D-Link DIR-818LW Rev.A 2.05.B03 and DIR-860L Rev.B 2.03.B03 devices, unauthenticated remote OS command execution can occur in the soap.cgi service of the cgibin binary via an "&&" substring in the service parameter. NOTE: this issue exists because of an incomplete fix for CVE-2018-6530.
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 818lw Firmware: 2.05.b03
- D-Link Dir 860l Firmware: 2.03.b03