Pre-Account Takeover is a type of attack that we very often carry out during our audits. Although it is only possible in very specific situations, the possibilities for malicious exploitation are becoming increasingly common, with potentially serious consequences for data security.

In this article, we present how a Pre-Account Takeover attack works. We will also look at the specifics of the attack, using a concrete example, as well as security best practices for countering the risk.

Security vulnerabilities are a major risk for modern web applications, potentially exposing sensitive user data and corporate infrastructures to malicious attacks.

One of the most feared vulnerabilities is Remote File Inclusion (RFI). This attack technique enables an attacker to inject and execute arbitrary code hosted on a remote server.

Prototype pollution vulnerabilities are specific to JavaScript. They can be exploited on both the server and client sides. These vulnerabilities allow attackers to execute malicious code or steal data.

It is therefore crucial to understand and address these vulnerabilities. This article details the principles of prototype pollution vulnerabilities, server-side and client-side exploits, as well as the measures to implement to counter these attacks.

Account takeover is a common practice that threatens the security of users and their data. The impact on victims depends on the type of account targeted. It can be minor if it’s a customer loyalty account but becomes critical for a corporate administrator account.

Attacks use a variety of techniques, often based on large-scale campaigns to steal as many credentials as possible. However, there are also application vulnerabilities enabling more targeted account takeover. The presence of these vulnerabilities represents a major risk for companies, especially if an administrator account is compromised.

In an office environment, user workstations generally use Windows operating systems and therefore authenticate using protocols developed by Microsoft.

And to centralise authentication management, Microsoft provides its Active Directory (AD), which is based on the Kerberos protocol. However, some machines do not implement this protocol and some networks simply do not have an Active Directory. In these cases, there is the NTLM protocol, which can work between two machines without AD or via the Netlogon process.

You’ve probably heard about the arrival of LLMs in a big way, at least with ChatGPT.

LLM (Large Language Model) refers to language processing models. These models are trained to perform all types of linguistic tasks: translation, text generation, question answering, etc.

Often, when we hear about Java serialization, we find resources or challenges that only talk about generating and executing ysoserial payloads.

In some situations, this can work. However, as soon as a customer is aware of this possibility, rather than using a more secure format, they generally prefer to use a library such as notsoserial which prevents the deserialization of unauthorized classes.

In the space of 5 years, the number of Denial of Service (DoS) attacks has almost doubled. The result is the paralysis of tens of millions of web platforms and the loss of thousands or even millions of euros by victim organisations.

Companies such as Amazon and GitHub have already been affected by this type of attack. One of the best-known attacks is MIRAI, which used a botnet of nearly 100,000 hijacked machines to make Dyn’s services unavailable in 2016.