A critical flaw in NetGear routers exposes them to cyber attacks

The security Expert Peter Adkins discovered a serious Information disclosure vulnerability that affects several Netgear wireless routers.

The researcher Peter Adkins discovered that several wireless routers produced by Netgear are affected by serious vulnerability that could allow an unauthenticated attacker to access sensitive data from the network device. By exploiting the vulnerability a hacker could also extract administrator passwords, the name and access keys for the wireless networks configured on the device, and details about the device including its model, firmware version and serial number, as explained in a post published on the Full Disclosure mailing list last week.

In a possible attack scenario, a threat actor could exploit the vulnerability after infecting a computer on the same LAN segment with a malware. Another possibility it to run a cross-site request forgery (CSRF) attack to trick users into visiting a site that forces their browsers to forward a malicious request to a vulnerable Netgear router on the local networks.

Wireless routers are a privileged target for hackers, threat actors compromise them to conduct several illegal activities, including traffic manipulation or run DDoS attack.

The security advisory published by the researcher Peter Adkins also includes a proof-of-concept, the experts confirmed to have tried to contact Netgear, but the technical support department of the company rejected its report.

The flaw in the Netgear devices can be exploited both over local area networks and over the Internet if the devices have the remote administration enabled.

Adkins explained that the vulnerability affects a service designed to interact with Netgear Genie, an application that allows users to monitor and control their routers directly from a mobile device (i.e. smartphones or a tablet).

The researcher discovered that sending HTTP requests to the SOAP service with a blank form and a “SOAPAction” header is possible to extract sensitive data from a vulnerable Netgear device.

“At first glance, this service appears to be filtered and authenticated; HTTP requests with a `SOAPAction` header set but without a session identifier will yield a HTTP 401 error. However, a HTTP request with a blank form and a `SOAPAction` header is sufficient to execute certain requests and query information from the device. As this SOAP service is implemented by the built-in HTTP / CGI daemon, unauthenticated queries will also be answered over the internet if remote management has been enabled on the device. As a result, affected devices can be interrogated and hijacked with as little as a well placed HTTP query.” wrote Adkins.

The security alert confirms that the following Netgear devices are affected

• NetGear WNDR3700v4 – V1.0.0.4SH
• NetGear WNDR3700v4 – V1.0.1.52
• NetGear WNR2200 – V1.0.1.88
• NetGear WNR2500 – V1.0.0.24

Additional platforms believed to be affected are:

• NetGear WNDR3800
• NetGear WNDRMAC
• NetGear WPN824N
• NetGear WNDR4700

Adkins recommends the following action to mitigate the risk:

• Ensure remote / WAN management is disabled on the affected devices.
• Only allow trusted devices access to the local network.

Pierluigi Paganini

(Security Affairs –  Netgear router, hacking)