CVE-2018-21221

Vulnerability

A buffer overflow vulnerability exists in certain NETGEAR devices, specifically the D3600, D6000, and R9000 models, before firmware versions 1.0.0.67 (for D3600 and D6000) and 1.0.2.52 (for R9000) [1]. The vulnerability can be triggered without authentication, making it remotely exploitable by an unauthenticated attacker [1]. The exact component or code path is not fully disclosed in the available references, but the advisory indicates it is a pre-authentication buffer overflow [1].

Exploitation

An attacker can exploit this vulnerability from an adjacent network (AV:A) without needing any authentication or user interaction [1]. The CVSS vector indicates low attack complexity (AC:L) and no privileges required (PR:N) [1]. The advisory does not provide detailed exploitation steps, but the buffer overflow can be triggered by sending crafted network traffic to the affected device [1].

Impact

Successful exploitation grants an attacker high impact to confidentiality, integrity, and availability (C:H/I:H/A:H) [1]. This means the attacker could potentially execute arbitrary code, gain full control of the device, or cause a denial-of-service condition [1]. The CVSS base score is 8.8 (High) [1].

Mitigation

NETGEAR has released fixed firmware versions: 1.0.0.67 for D3600 and D6000, and 1.0.2.52 for R9000 [1]. Users are strongly recommended to download and install the latest firmware from NETGEAR Support [1]. No workarounds are provided; the only mitigation is to apply the firmware update [1]. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog as of publication [1].