CVE-2021-27256

Name of the Vulnerable Software and Affected Versions: NETGEAR R7800 version 1.0.2.76

Description: This issue allows network-adjacent attackers to execute arbitrary code on affected installations. Although authentication is required to exploit this issue, the existing authentication mechanism can be bypassed. The specific flaw exists within the handling of the rc service parameter provided to "apply save.cgi". The issue results from the lack of proper validation of a user-supplied string before using it to execute a system call. An attacker can leverage this issue to execute code in the context of root.

Recommendations: For NETGEAR R7800 version 1.0.2.76, as a temporary workaround, consider disabling the "apply save.cgi" endpoint until a patch is available. Restrict access to the rc service parameter to minimize the risk of exploitation. Avoid using the rc service parameter in the affected "apply save.cgi" endpoint until the issue is resolved. At the moment, there is no information about a newer version that contains a fix for this issue.