A critical vulnerability in NETGEAR’s ReadyNAS network attached storage devices can allow attackers to gain root access without authentication, according to a warning from the Tripwire Vulnerability and Exposure Research Team (VERT).
Tripwire’s security researcher Craig Young describes the flaw as a command injection issue that occurs because of a failure to sanitize user-controlled input. “This instance is particularly severe because it can be triggered without authentication,” Young warned in an advisory.
“The consequence is that an unauthenticated HTTP request can inject arbitrary Perl code to run on the server. Naturally, this includes the ability to execute commands on the ReadyNAS embedded Linux in the context of the Apache web server,” Young explained.
“[This issue allows] complete root access from a single, unauthenticated HTTP request,” he warned.
NETGEAR shipped an update to correct the issue but Tripwire’s research team found that the documentation on the severity of the vulnerability was very limited and caused many ReadyNAS users to skip application of the patch.
Using the Shodan search tool, Young found more than 10,000 public IP addresses running vulnerable versions ReadyNAS. “Based on a sample size of 2,000 hosts, approximately 73% of the Internet exposed ReadyNAS are running [the vulnerable] RAIDiator firmware prior to 4.2.24,” he said.
“If you are running ReadyNAS and you have not already updated, it is imperative that you do so ASAP, especially if your ReadyNAS web interface is one of the thousands that are directly accessible from the public Internet,” Young warned.
In the advisory, Young said the attack surface is reduced when the ReadyNAS web interface is not exposed to the Internet but cautioned that the flaw can be exploited via specially crafted web pages or even e-mail messages.
Tripwire reported the issues to NETGEAR starting last November, leading to the release of patches in July. However, Young said NETGEAR released firmware updates without proper warnings about the seriousness of the issues.
“The only mention of security concerns were in the firmware release notes. There’s just one line: ‘Updated Frontview to fix security issues.’ Without knowledge of the specific vulnerabilities, customers feel no sense of urgency about installing the update,” he added.