Vulnerabilities > CVE-2020-27866 - Authentication Bypass Using an Alternate Path or Channel vulnerability in Netgear products
Summary
This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of NETGEAR R6020, R6080, R6120, R6220, R6260, R6700v2, R6800, R6900v2, R7450, JNR3210, WNR2020, Nighthawk AC2100, and Nighthawk AC2400 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the mini_httpd service, which listens on TCP port 80 by default. The issue results from incorrect string matching logic when accessing protected pages. An attacker can leverage this in conjunction with other vulnerabilities to execute code in the context of root. Was ZDI-CAN-11355.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Directory Indexing An adversary crafts a request to a target that results in the target listing/indexing the content of a directory as output. One common method of triggering directory contents as output is to construct a request containing a path that terminates in a directory name rather than a file name since many applications are configured to provide a list of the directory's contents when such a request is received. An adversary can use this to explore the directory tree on a target as well as learn the names of files. This can often end up revealing test files, backup files, temporary files, hidden files, configuration files, user accounts, script contents, as well as naming conventions, all of which can be used by an attacker to mount additional attacks.
- Removing/short-circuiting 'guard logic' Attackers can, in some cases, get around logic put in place to 'guard' sensitive functionality or data. The attack may involve gaining access to and calling protected functionality (or accessing protected data) directly, may involve subverting some aspect of the guard's implementation, or outright removal of the guard, if possible.