Quantum Secular Labs / Blog / Advisories
CVE-2018-1164: Zyxel P 870h 51 Firmware: Authentication bypass
CVE-2018-1164 is rated critical with a CVSS v3.0 base score of 9.8 and NVD lists Zyxel P 870h 51 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
This vulnerability allows remote attackers to cause a denial-of-service condition on vulnerable installations of ZyXEL P-870H-51 DSL Router 1.00(AWG.3)D5. Authentication is not required to exploit this vulnerability. The specific flaw exists within numerous exposed CGI endpoints. The vulnerability is caused by improper access controls that allow access to critical functions without authentication. An attacker can use this vulnerability to reboot affected devices, along with other actions. Was ZDI-CAN-4540.
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-306: Missing Authentication for Critical Functionality
The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
CWE-732: Incorrect Permission Assignment for Critical Resource
The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.
Affected products
- Zyxel P 870h 51 Firmware: 1.00\(awg.3\)d5