Scams & malware

Can an online ad install spyware on your device?

You expect an online ad to try to sell you something. You do not expect it to break into your device. But in October 2026, researchers showed that spyware had reached dozens of devices through ordinary-looking online ads, with no click needed. It sounds alarming, but the full picture is calmer. Here is what happened, who was really at risk, and the simple steps that help.

What happened

In October 2026, Citizen Lab published a report on a new way spyware reached its targets. Citizen Lab is a research group at the University of Toronto that studies digital spying. It found that at least 45 devices belonging to staff at the news network Al Jazeera were targeted in 2024 and 2025. The affected devices were Windows computers. The spyware came from a company called Candiru, which sells its tools to governments. The way in was unusual: targeted online ads. The researchers called the technique “AdFection.”

How an ad can do this

Online ads are not just pictures. Many carry a small piece of code. Advertisers can also aim an ad at a very narrow audience. In this case, an advertising company called Discover-Tech placed ads aimed at chosen people. When an ad loaded, it quietly sent details about the device to a server. If the device belonged to a chosen target, the attack moved to the next step and tried to install spyware.

The person did not have to click anything. Sometimes the ad loaded in the background, so the person may never have seen it. That is what “zero-click” means: there is nothing for you to notice and nothing for you to avoid.

Who was actually at risk

The targets were staff at a major news network. That fits a pattern we described in our article on Pegasus spyware. Tools like this are costly, and they are used on people a government wants to watch, such as reporters, activists and lawyers.

If you are not in a group like that, the practical risk to you is very low. The ads appeared on many websites and apps, but only chosen targets were sent the spyware. This is worth saying plainly, because the goal here is calm, not fear.

What spyware can see

Once spyware is on a device, it can read messages, photos, notes and files. It may even switch on the microphone or camera. In short, it sees what your device sees. This is different from everyday malware like an infostealer, which is spread widely and usually needs you to install something.

The simple steps that help

Keep everything updated. That means your phone, your computer and your web browser. Attacks like this depend on flaws that updates fix, so updating promptly is the single most effective thing you can do. Restart your devices now and then, too. Some spyware does not survive a restart.

Load fewer ads. A content blocker in your browser reduces how many ads appear at all, and it also cuts tracking. Choosing fewer free apps that are full of ads helps in the same way.

If you may be a target, turn on Lockdown Mode on your iPhone, iPad or Mac, or Advanced Protection on Android. These settings switch off some of the features that attacks like this abuse. If you ever get a threat warning from Apple or Google, take it seriously and seek help from a group like Access Now’s Digital Security Helpline.

Where Sealby fits

We will always be straight about this. Sealby cannot stop a government-grade attack on your device, and no app can fully protect what is on screen once a device is taken over. The defenses that matter most are updates and, for people at risk, Lockdown Mode or Advanced Protection. What Sealby does is give your most sensitive photos, notes and files a home of their own. They stay encrypted on your device, open only with your own PIN, pattern or passphrase, and stay out of the shared camera roll that other apps can see. It is one honest layer among several, not a magic shield.

This is general education, not security advice. It describes a recent research report whose details may be updated, and threats and device settings change over time. Check current, reputable sources and the settings on your own devices.

Quick answers

Can a normal ad really infect my device?

In this case, the ad carried hidden code that ran as soon as the ad loaded, with no click needed. But this was not a normal ad campaign. It was set up to reach specific people, through an ad company that the researchers say spyware makers used. The ordinary ads you see every day are not built to do this.

Should I worry about this?

For most people, no. This kind of spyware is costly and is aimed at chosen targets, such as journalists. The best habit for everyone is to keep your phone, computer and browser updated, because updates close the flaws these attacks depend on.

Will an ad blocker protect me?

It can help. A content blocker reduces how many ads load at all, and it also cuts tracking. But it is not a complete shield. Updates matter more, and people at higher risk should also use Lockdown Mode or Advanced Protection.

Can an encrypted app stop this kind of spyware?

Not on its own. If a device is fully taken over, an attacker can see content while you have it open, inside any app. The best defense is keeping the spyware off the device in the first place. An encrypted vault still helps by keeping your most sensitive files locked away while you are not using them.

Who was behind the attacks?

The researchers linked the spyware to a company called Candiru, which sells its tools to governments. They said they could not tell which government used it. The ads were placed through an advertising company called Discover-Tech. After working with the researchers, Google cut that company off from its ad platform.

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