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“IP address key in countering brute force cyber attacks” asserts Verizon

Verizon’s 2020 Data Breach Investigations Report shows that 80% of the breaches caused by hacking involve brute force tactics or the use of lost or stolen credentials. Content Management Systems (CMS) are the usual targets of brute force attacks as over 39% of all websites run on WordPress, the most popular CMS of all.

Cyber criminals choose to attack pages built on CMS because they usually have the same admin page URL across websites and the default login credentials are identical, making these pages a vulnerable target. However, developers and admins can mitigate the risk by reducing IP access to the admin site login page. 

A brute force attack (sometimes referred to as brute force ‘cracking’) is a method of trying various possible passwords until the right one is found. Despite being old, the method is still widely used by hackers who attempt to gain access to a valid account. It allows bad actors to compromise the whole website and use it as a part of their network.

With more people now working remotely amid the ongoing Coronavirus pandemic, the number of brute force attacks against remote desktops via Windows’ Remote Desktop Protocol (RDP) has soared. Indeed, that number reached nigh on 100,000 attacks each day during last April and May.

In the worse case scenario, criminals can steal important data, such as passwords, pass phrases, e-mail addresses or PINs. They also use compromised websites for various fraud schemes, whereas pages themselves can be included in Google’s #blacklist’ and, as such, become invisible in search results.

Failed authentications

“Developers and admins can indicate an ongoing brute force attack by looking at failed authentications,” explained Juta Gurinaviciute, CTO at NordVPN Teams. “If the same IP address unsuccessfully tries to login to various accounts or different IP addresses are attempting to access one account in a short period of time, this is a clear sign of a data breach attempt.”

As the IP address is one of the indicators of a cyber attack, it can also be a cure. On that basis, it’s wise for companies to reduce the ‘surface area’ available for attack and limit access to the login page. This can be done by making use of IP allowlist, blocklist and fixed IP techniques.

Previously known as whitelist, IP allowlist is a set of IP addresses that have access to a specific website. The developer can specify which IP addresses are allowed to reach an admin login page and perform actions there. It’s also possible to indicate a range of IP addresses that can obtain authorised access. The latter solution is useful within bigger organizations or if numerous people require access to the website. 

However, Internet Service Providers may be changing IP addresses frequently and, as a result, the allowlist might constantly become outdated. This solution only works, then, if there’s a pool of limited IP addresses in use or the changes take place within the specific range.

Intrusion prevention frameworks

Also known as blacklist, IP blocklist is the exact opposite of the previously mentioned IP address directory as it blocks access to websites from the specified IP addresses. As this is difficult to do on a manual basis, admins and developers may employ intrusion prevention frameworks such as Fail2Ban. The framework automatically blocks IP addresses after a few unsuccessful authorisation attempts.

On the other hand, website owners can block the particular IP addresses as well as the whole IP address range. If a company notices that suspicious attacks from specific IP addresses persist, the management team should consider adding them to the blocklist.

Further, IP blocklist can also be used for geo-blocking as the IP address carries the information about where the request was sent from in the first instance. 

The third solution for minimising unauthorised access is the fixed IP method. As already mentioned, developers can limit availability of the login page to a set of trusted IP addresses. With fixed IP, they reduce the risk of IP sharing when a number of devices use the same IP address. This often leads to the ‘bad neighbour effect’ as, due to the deeds of other users, IP addresses end up in various blocked or spam lists.

The fixed IP method can be offered by Internet Service Providers and VPN services alike, but the latter ensures browsing privacy as an additional benefit.

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