Browsing the Internet may be an everyday and seemingly harmless activity, but it is riddled with cyber threats of all kinds. One of the most insidious and least understood is the malvertising, a technique used by cybercriminals to take advantage of the online advertising and attack unsuspecting users. Although this term is unfamiliar to many people, its impact can be devastating for both individuals and businesses.
Malvertising combines cunning and technology to infiltrate legitimate ad networks and use ads as a vehicle to distribute malicious software, redirect to fraudulent sites or collect sensitive user information. It is essential to be informed about their methods, scope and, above all, how they are used. protect ourselves from this threat camouflaged in something apparently as harmless as an advertisement.
What is malvertising?
The term malvertising, a contraction of the English words “malicious advertising”, describes a practice that consists of manipulating online advertisements with the aim of infecting devices or redirecting users to malicious websites. malicious websites. These ads are often embedded in legitimate ad networks and are then displayed on trusted websites that users choose to visit regularly.
The most alarming thing about malvertising is that, in many cases, It is not necessary to interact with the ad for the device to be compromised. It is enough for the page hosting the ad to be loaded in the browser for the attack to be initiated by automatic downloads or redirects.
This type of attack allows cybercriminals to penetrate layers of to maximise security and your enjoyment. in operating systems and browsers, compromising both the privacy and integrity of user data. In addition, their presence is difficult to detect because it does not require the ad to be displayed in a suspicious manner, as they usually have the appearance of a everyday advertising.
Key differences between malvertising and adware
Malvertising is often confused with adware, as both practices are related to the malvertisingHowever, there are fundamental differences between the two:
- Malvertising: uses legitimate advertising networks to insert malicious ads that infect users' devices without warning. The attack does not necessarily require user interaction.
- Adware: On the other hand, it pre-resides on the infected device and bombards the user with unwanted ads to generate revenue or collect data.
While malvertising primarily affects through ad manipulation, adware is already installed on victims’ devices when it begins to operate. Both are dangerous, but malvertising, not relying on prior user interaction, can be even harder to prevent.
How does malvertising work?
Malvertising takes advantage of the complexity of online advertising ecosystem to carry out their attack. The basic process behind this technique is described below:
- Cybercriminals acquire advertising space: They buy advertising space on legitimate platforms, just like any advertiser would.
- Insertion of malicious code: The designed ads contain infected scripts or images that can directly harm the user or redirect them to dangerous pages.
- Distribution on trusted sites: Because the ads are served through well-known advertising networks, they end up appearing on trusted sites with high traffic.
- Action on loading: Some ads infect automatically when loaded by the browser, while others wait for a user to click on them.
This modus operandi makes malvertising an extremely stealthy and effective threat, capable of sneaking in even well-known websites, such as international news portals or popular streaming services.
Common malvertising techniques and examples
Cybercriminals have developed various strategies to exploit vulnerabilities and maximize damage. Here are some of the most well-known techniques:
- Steganography: It consists of hiding malicious messages or codes within images, making them go unnoticed by both users and security systems.
- Polyglot images: Not only do they hide malicious code, but they also contain the scripts necessary to execute it autonomously.
- Scareware: It uses alarming pop-ups that urge the user to download (supposedly useful) software that is actually malicious.
- Fake software updates: They trick users into downloading updates that are actually malware.
These are just some of the most common methods, and each of them aims to bypass the most common controls. ciberseguridad.
How to protect yourself from malvertising
Although malvertising is a sophisticated threat, there are several measures that can be taken to significantly reduce the risk:
- Install a ad blocker: These programs can prevent ads from loading in the first place, eliminating an entry route for attackers.
- Keep software up to date: Many attacks exploit known vulnerabilities in outdated software, so it is crucial to install updates regularly.
- Avoid unnecessary add-ons: Minimizing the use of browser plugins reduces potential attack windows for malvertising.
- Browse with caution: Using secure browsers and avoiding clicking on suspicious ads is also essential to staying safe.
In addition, educate users about the risks and the importance of these measures can make the difference between falling victim or staying protected.
Malvertising represents one of the many cyber threats that is constantly evolving, using clever techniques to compromise users' security. But keep in mind that it is something different from that misleading advertising that tries to convince us to click on a malicious link.
Therefore, the key to avoiding falling into these traps lies in the prevention, the constantly updated and the use of advanced security tools. Since even the most trusted sites can be used as a vehicle for these attacks, the best strategy is to always assume a cautious attitude. vigilant and proactive against any potential risk.