CVE-2017-18740

Vulnerability

Certain NETGEAR devices are affected by an incorrect configuration of security settings that results in insecure default credentials. This affects the following models: D3600 before 1.0.0.61, D6000 before 1.0.0.61, D6100 before 1.0.0.55, D7800 before 1.0.1.28, R6100 before 1.0.1.16, R7500 before 1.0.0.112, R7500v2 before 1.0.3.20, R7800 before 1.0.2.36, R9000 before 1.0.2.40, WNDR3700v4 before 1.0.2.88, WNDR4300 before 1.0.2.90, WNDR4300v2 before 1.0.0.48, WNDR4500v3 before 1.0.0.48, and WNR2000v5 before 1.0.0.58 [1]. The vulnerability is present in the default configurations shipped with these firmware versions.

Exploitation

An attacker with local network access (adjacent) can exploit this misconfiguration without needing authentication or user interaction [1]. The attack complexity is low. By connecting to the device's administrative interface, the attacker can use the default credentials (which are not disclosed in the advisory) to gain access.

Impact

Successful exploitation allows an attacker to obtain administrative access to the affected router or gateway [1]. This enables modification of device settings, interception of traffic, and potential further compromise of the local network. The CVSS v3 vector (AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L) indicates low confidentiality, integrity, and availability impact, with no privilege escalation beyond the router's administrative level.

Mitigation

NETGEAR has released fixed firmware versions for all affected models [1]. Users should upgrade to the latest firmware available from the NETGEAR Support website. The advisory does not provide any workaround; upgrading is the only recommended mitigation. No CVE is listed in the advisory for this issue beyond CVE-2017-18740.