Tabnabbing: this phishing threat can catch out even vigilant internet users

A threat that remains largely unknown to internet users.

Have you heard of tabnabbing? If not, this is worth your attention: it is a form of phishing capable of deceiving even cautious users who understand online risks. Here is what you need to know about this emerging threat, which is almost certainly already present in France.

How does tabnabbing work?

Spanish news outlet El Periodico has highlighted a warning issued by police on social media. In practice, this phishing technique specifically targets browser windows you have left open but are no longer using.

As the warning explains, “the cybercriminal will replace one of the websites you have open with a malicious copy that looks similar”. When you return to that page later, it may appear unchanged, yet it will actually be an imitation designed to obtain your personal or banking details. Just a moment of inattention can allow criminals to access and empty your account.

In short, cybercriminals set up a fraudulent website. Once a browser tab becomes inactive, a script swaps its content for a fake sign-in page, encouraging the user to enter details that are then stolen.

To prevent the worst, law enforcement agencies advise users to “keep open only the windows you are using and close all the others”. They also recommend that you “check again the URL of websites asking for your details”. If you have any doubts, close the window immediately and do not enter any of the requested information.

Phishing remains highly popular with cybercriminals

As we regularly explain on Presse-citron, phishing continues to be the most widely used hacking method among malicious actors. In a 2024 report, Europol noted that these attacks are becoming increasingly sophisticated. Tabnabbing clearly falls into this category, as virtually anyone can be caught out when they are not paying attention.

Remain alert when browsing and downloading

As Benzinga points out, the US Federal Bureau of Investigation (FBI) has warned internet users about the growing number of websites built to steal personal data or install malware. This is particularly common on untrustworthy free-download websites and streaming platforms. Staying vigilant is therefore more important than ever. Given these risks, we also recommend using an antivirus solution suited to your needs. To help you choose, feel free to consult our guide here.