NETGEAR Router Misconfiguration Opens The Door For Remote Attacks

Tenable Research has discovered a configuration issue impacting NETGEAR Nighthawk WiFi6 Routers commonly used in small offices and large homes. Organizations need to manually apply firmware updates.

Background

Tenable’s Zero Day Research Team began investigating NETGEAR’s Nighthawk router after reviewing the target list for the Zero Day Initiative’s (ZDI) Pwn2Own Toronto contest. Pwn2Own is a hacking competition where contestants are challenged with exploiting widely used software and devices using zero-day vulnerabilities. Pwn2Own complements ZDI’s broader purpose of collecting and reporting vulnerabilities to vendors, developing signatures for intrusion detection and thereby aiding defenders in reducing their exposure. The contest includes a special challenge, a small office/home office (SOHO) “smashup” to simulate a real world attack where an attacker would chain vulnerabilities in multiple devices in order to compromise a home network.

Because the targets chosen for the competition are widely used, there’s a much higher chance that security researchers have already picked them apart and found compelling vulnerabilities. While teams and individuals spend weeks researching and collecting their zero days, vendors may release last minute patches that can thwart attack chains. Unfortunately for the Tenable team, one of the most crucial vulnerabilities in our attack chain was patched by NETGEAR the day before the Pwn2Own registration deadline.

SOHO routers misconfigured by default

As the patch is publicly available, we are free to talk about the vulnerability and its impact. A network misconfiguration present in versions prior to V1.0.9.90 of the firmware inadvertently allowed unrestricted communication with any services listening via IPv6 on the wide-area network (WAN), internet facing port of the device. For example, the secure shell protocol and telnet operate on ports 22 and 23, respectively. Without the patch, an attacker can interact with services from the WAN port that are only intended to be accessible by those on the LAN side of the network, which increases organizations’ cyber risk.

As noted in the SOHO mashup notes from Pwn2Own, the first step in the attack chain is to compromise one of the target routers over the WAN interface. With this patch release, we unfortunately had to withdraw our submission for the NETGEAR Nighthawk WiFi6 Router. However on the plus side, a concerning attack vector has now been closed.

Solution

NETGEAR has released firmware version 1.0.9.90 to address the misconfiguration we found. This firmware release may include other fixes, we did not analyze the firmware for all changes.

It’s important to note that, while the team was able to locate the firmware update linked on NETGEAR’s website, we found our test devices did not automatically update to this firmware release, even with the device’s auto-update feature.

NETGEAR customers who rely on the auto-update or “Check for Updates” mechanisms of these devices are likely to remain vulnerable to this issue and any other issues teased over the coming days of Pwn2Own Toronto 2022.

Additional Information

• Visit the Tenable Tech Blog on Medium to read researcher Jimi Sebree’s in-depth write-up about this vulnerability.
• Tenable Research Advisory