Attack Techniques
What Is Malvertising?
Malvertising (malicious advertising) is the use of online advertisements to distribute malware and compromise user systems. Attackers inject malicious code into legitimate advertising networks, banner ads, video content, or ad pixels.
Malvertising (malicious advertising) is the use of online advertisements to distribute malware and compromise user systems. Attackers inject malicious code into legitimate advertising networks, banner ads, video content, or ad pixels. The infection can occur without user action—through "drive-by downloads" that exploit browser vulnerabilities—or require a click or interaction. Malvertising targets users through trusted advertising platforms, making it particularly effective at evading detection.
How does malvertising work?
Malvertising attacks follow a multi-stage delivery chain designed to maximize reach while evading security controls.
Attackers begin by compromising advertising networks or websites to inject malicious code into ad creative, including banner images, video content, and tracking pixels. These infected ads enter the ad ecosystem through weaknesses in verification processes or by targeting smaller ad networks with less rigorous security controls.
Once infected ads are distributed through legitimate advertising channels, the exploitation phase begins. Browser vulnerabilities are exploited via "drive-by downloads" without user interaction, or ads use cloaking techniques to hide malicious URLs behind legitimate-looking code.
Exploit kits used in malvertising scan the target system—fingerprinting via HTTP requests—to detect vulnerable plugins or software versions, then match with available exploits. Malvertisers evade ad scanners using cloaking, which presents legitimate-looking code to security scanners while hiding real malicious URLs from detection.
When executed, payloads deploy ransomware, spyware, bots, infostealers, backdoors, or fileless malware using PowerShell or JavaScript for in-memory execution. Criminals profit via data exfiltration, ransom demands, cryptocurrency mining, or botnet control.
According to SentinelOne (2024), the malvertising attack chain operates with minimal user interaction, making it significantly more dangerous than phishing campaigns that require explicit user action.
How does malvertising differ from related threats?
Aspect | Malvertising | Ad Malware | Phishing |
|---|---|---|---|
Vector | Legitimate ads with injected code | Ad-related malware exclusively | Email/social engineering links |
User Action | Not required (drive-by) | Often requires click | Required (credential entry) |
Scope | Reaches millions via ad networks | Narrower distribution | Targeted or mass campaigns |
Payload Type | Full malware suite | Various malware families | Credential theft, initial access |
Detection Difficulty | High (trusted networks) | High (ad obfuscation) | Moderate (URL inspection) |
Ideal for | Mass malware distribution with minimal targeting; exploiting trust in ad networks | Campaigns focused specifically on ad-delivered payloads | Targeted credential theft requiring user interaction and trust |
Malvertising differs fundamentally from traditional phishing attacks. Phishing requires user interaction—clicking links and entering credentials—while malvertising can infect systems without any user action through drive-by download techniques. The scope of malvertising is considerably broader, as a single infected ad distributed through major advertising networks can reach millions of users.
Ad malware refers to malware specifically distributed through advertising channels but may require explicit user clicks or interaction. Malvertising encompasses both passive infection vectors (drive-by downloads) and click-based delivery, making it more dangerous.
The detection difficulty for malvertising is notably high because it operates within trusted advertising networks and legitimate websites, bypassing many traditional security filters that focus on email-based threats or suspicious domains.
Why does malvertising matter?
Malvertising represents one of the most effective malware distribution mechanisms because it exploits the trust users place in legitimate websites and advertising platforms.
The United States experienced a 42% surge in malvertising campaigns in the past year, according to Malwarebytes (2024). Globally, SentinelOne detected 6.06 billion malware attacks worldwide in 2023, with a substantial portion delivered through malicious advertising.
Malwarebytes reports that 560,000 new malware pieces are detected daily on average. The advertising ecosystem's programmatic buying model creates opacity in the supply chain, allowing malicious ads to reach legitimate sites before detection occurs.
GeoEdge data from Q4 2021 showed that 1 in 125 ad impressions were dangerous or disruptive. While industry-wide security violation rates dropped to 0.21% in recent 2024 data according to GeoEdge (2024), the absolute number of malicious impressions remains significant given the scale of digital advertising.
The financial impact is substantial. Malwarebytes (2024) reports that $1.3 billion was generated via piracy site malvertising alone. Magecart attacks on ecommerce—which often use malvertising as a delivery mechanism—increased approximately 103% in H1 2024 according to SentinelOne.
A notable 2025 campaign demonstrates the continuing threat: the UNC6032 threat group launched a malvertising campaign impersonating AI video tools such as Luma AI and Canva Dream Lab via Facebook and LinkedIn ads, deploying Python-based infostealers and backdoors, according to Malwarebytes and search results (2025).
GeoEdge (2024) reports that 29% of malvertising attacks in Q1 2024 used misleading offers, up from 26% in 2023, indicating attackers are refining social engineering tactics alongside technical exploitation.
What are the limitations of malvertising?
Malvertising faces several operational and technical constraints that limit its effectiveness and lifespan.
Attackers require presence in legitimate ad networks, and infected campaigns are typically banned quickly upon detection. Drive-by downloads fail against updated browsers with modern sandbox protections, significantly reducing the attack surface. Exploit kits require specific vulnerable software versions, and effectiveness decreases as users patch systems.
Cloaking detection is improving through machine learning in ad verification tools. Security researchers and advertising platforms are deploying behavioral analysis systems that identify suspicious ad behavior patterns, even when initial scans show clean code.
Defense gaps remain significant. Programmatic ad buying creates opacity in the supply chain, allowing malicious ads to reach legitimate sites before detection. Ad verification tools have imperfect detection rates; one Supply-Side Platform (SSP) recorded 1 in 9 impressions as threats on May 14, 2024, according to GeoEdge (2024).
Users often disable or ignore browser warnings on security prompts, reducing the effectiveness of browser-based protections. The mobile ad ecosystem has weaker verification standards than desktop, creating an expanding attack surface as mobile usage grows.
Despite improving detection capabilities, the fundamental challenge remains: advertising networks must balance security with performance, and the milliseconds required for real-time bidding limit the depth of security scanning possible before ad delivery.
How can organizations defend against malvertising?
Organizations should implement multiple layers of defense to protect against malvertising attacks.
Ad blockers block malvertising ads entirely from loading, providing the most complete protection. However, many organizations cannot deploy ad blockers due to business requirements or legitimate advertising needs.
Software updates are critical. Organizations must maintain current operating system, browser, and plugin versions to prevent drive-by downloads. According to SentinelOne and CrowdStrike, patched systems are significantly more resistant to malvertising exploitation.
Web filtering at the network level blocks known malicious ad domains and command-and-control infrastructure. DNS-based filtering can prevent connections to malware distribution points even if initial ad delivery succeeds.
Browser security measures include enabling sandboxing, auto-update features, and exploit protection through tools like Windows Defender Exploit Guard. Modern browsers include significant protections against drive-by downloads, but these protections must be enabled and maintained.
Email and user training should educate users on suspicious ad recognition and the risks of clicking unknown ads, particularly on piracy sites or questionable websites. Malwarebytes and Fortinet emphasize that user awareness reduces risk even when technical controls fail.
Security monitoring should track network traffic for indicators of compromise, including command-and-control callbacks and data exfiltration patterns. Behavioral detection is more effective than signature-based detection for identifying novel malvertising campaigns.
Endpoint protection should deploy behavioral detection tools to catch fileless malware execution. CrowdStrike and SentinelOne recommend endpoint detection and response (EDR) solutions that monitor process behavior rather than relying solely on file signatures.
Publishers should use ad verification tools and Supply-Side Platforms (SSPs) with strong security records. GeoEdge recommends real-time ad verification that analyzes ad behavior during delivery, not just pre-delivery scanning.
Incident response procedures should include immediate isolation and scanning of infected systems, along with monitoring for lateral movement. McAfee and Fortinet emphasize that rapid detection and response limits damage from successful malvertising infections.
FAQs
Can malvertising infect me without clicking the ad?
Yes. Drive-by download attacks exploit browser vulnerabilities to execute malicious code when the ad loads, without user interaction. According to SentinelOne (2024), these attacks leverage vulnerabilities in browsers, plugins, or operating systems to install malware simply by rendering the infected advertisement. Modern browsers have improved protections, but unpatched systems remain vulnerable to zero-day exploits and known vulnerabilities that users have not yet patched.
Which brands are most impersonated in malvertising campaigns?
According to Malwarebytes (2024), the top five impersonated brands are Amazon, Rufus, Weebly, Notepad++, and TradingView. The most commonly abused hosts for malware distribution include Dropbox, Discord, 4sync, Gitlab, and Google. Attackers impersonate trusted brands and use legitimate cloud services to host malware because users trust these platforms and security filters often whitelist them, allowing malicious content to bypass detection.
How do malvertisers evade ad network detection?
Cloaking hides malicious URLs in legitimate-looking code that passes security scanners. According to Huntress, NordVPN, and GeoEdge, attackers exploit weaknesses in smaller ad networks or pose as legitimate advertisers to inject malicious code into the advertising supply chain. The cloaking technique presents different content to security scanners than to actual users, allowing malicious ads to pass verification while still delivering exploits to victims.
What happens after malvertising infection?
Payloads vary significantly based on attacker objectives. According to SentinelOne (2024), malvertising can deploy data theft tools, ransomware encryption, botnet control software, cryptocurrency mining tools, or spyware installation. Many modern malvertising campaigns use fileless techniques employing PowerShell or JavaScript for in-memory execution, evading file-based antivirus detection. The attack objective depends on the threat actor, ranging from immediate financial gain through ransomware to long-term espionage through persistent backdoors.
Why is malvertising harder to detect than email malware?
Malvertising operates within trusted ad networks and legitimate websites, bypassing email filters entirely. According to Malwarebytes and CrowdStrike, user trust in advertisements on reputable sites is higher than trust in unsolicited emails, increasing the likelihood of interaction with malicious content. The programmatic advertising supply chain creates verification blind spots—ads move through multiple intermediaries between advertiser and publisher, with limited security inspection at each stage. The real-time nature of ad delivery limits the time available for thorough security analysis before ads reach users.
