AdSecure analyzed over 43 million violation prevention scans conducted on client campaigns in Q3, 2025. In our last article, we uncovered the 10 largest increases in violation attempts in Q3; however, there was a large increase in malvertising attempts in quarter three across all violation types. In this article, we will explore seven more violations that increased in this quarter.

Let’s take a look at the most common violations in user security, experience, and advisory.

User Security Violations

These violations pose a direct threat to the user’s safety, potentially leading to financial loss, identity theft, or malware installation. This category saw some of the most significant increases.

Malicious URL: Virustotal

Malicious URLs contain unsolicited content such as spam, phishing schemes, and drive-by exploits, which can lure unsuspecting users into scams, resulting in monetary loss, theft of private information, and malware installation. This detection is specifically based on violations reported by VirusTotal regarding malicious URLs. In the third quarter of 2025, when compared to Q2, the number of detections for these violations increased by 33.4%.

Scareware

Scareware refers to advertisements that falsely claim a user’s computer is infected with a virus and that antivirus software is needed. Ironically, these ads may contain malware themselves, which can lead to computer damage, expensive repairs, or identity theft. Scammers often imitate legitimate warning alerts from reputable security companies to gain users’ trust. In the third quarter of 2025, we observed a 29.8% increase in the frequency of this type of violation when compared to Q2.

User Experience Violations

These violations negatively impact the user’s browsing experience, often by disrupting navigation, forcing unwanted actions, or causing performance issues.

Auto-redirect app store

Ads that automatically redirect the user to an App Store without requiring any user interaction (a click or tap). This is highly disruptive to the user’s browsing flow. In Q3 2025, we saw an increase of +11.5% in detections for Q2.

Heavy Ad

These are ads that violate Google’s heavy ad intervention policy and are subsequently blocked by the Chrome browser. An ad is considered “heavy”.

What’s the criteria for a heavy ad:

  • Consumes more than 4MB of network bandwidth.

  • Uses the CPU for 15 seconds or more within a 30-second window.

  • Uses the CPU for 60 seconds or more in total.

  • Heavy ads severely degrade the user experience and website performance.

In Q3 2025, this detection increased by +7%

User Advisory Violations

These violations are typically related to technical non-compliance or flags indicating a potential (though not always definitive) link to malicious or suboptimal activity, allowing users to make an informed decision.

IAB: Ad File Compression

To optimize delivery size, ad assets should be delivered in compressed formats (like gzip) to comply with IAB standards. This detection flags ads that are not delivered in a compressed format, thus violating IAB guidelines and potentially leading to slower load times. There was an increase of uncompressed ads by +18.7% in Q3 2025.

Suspicious TLD

Detection of Top-Level Domains (TLDs) that are frequently used by cybercriminals for malicious activities like spam e-mailing, scams, malware distribution, and phishing attacks. While not all flagged domains are definitively malicious, the policy is to inform the user of their potential relationship to harmful activity. This detection increased by +16% in Q3.

IAB: Ad Dimension

Violation of IAB standards regarding recommended ad dimensions, which are designed to ensure sufficient advertising across multiple screen sizes and contribute to revenue. The recommended range is 100x200 - 150x300. Ads outside this range are flagged for non-compliance. This violation had an increase of 2.3%, although it’s not as big as some of the other violations, it can really affect ad performance. If you are using AdSecure and you would like to track the IAB compliance of your advertisers, enable the IAB standards feature in the Admin Panel.

How to prevent malvertising attempts on your network

It is crucial to invest in a strong compliance team and effective ad security software to protect your ad supply chain and users from harmful advertisements. If you are looking for an ad security software to protect your online platform, contact our team today to learn how to start securing your ad network or website!