Malvertising

12th August 2025 | Cybrary

Malvertising is short for malicious advertising. It refers to the use of online ads to deliver malware to users’ devices. Cybercriminals buy ad space on legitimate websites (sometimes through third-party ad networks) and insert malicious code into the ads. When someone views or clicks on these ads, the code can redirect them to a malicious website, exploit vulnerabilities in their browser or plugins, or download malware onto their system, all without the user necessarily realizing what’s happening.

What Malvertising Means for SMBs

For small and medium-sized businesses, malvertising poses significant risks:

Unintentional Exposure to Malware
Employees browsing legitimate websites during work hours can be compromised by malicious ads, even without visiting suspicious sites.
Data Breaches and Ransomware
Malvertising can deliver ransomware, keyloggers, and other malware that lead to stolen data, system lockouts, and costly downtime.
Reputation Damage
If an SMB’s own ads or website become compromised through an ad network, it can erode trust with customers and partners.
Financial Losses
Recovering from a malvertising incident may involve system restoration, incident response costs, regulatory fines, and loss of productivity.
Increased Attack Surface
SMBs with limited IT staff or outdated systems are more vulnerable, as they may lack the tools to detect and block malvertising campaigns in real time.

Bottom line: For SMBs, malvertising is dangerous because it weaponizes trusted ad networks and popular sites, bypassing the “don’t visit shady websites” rule. Protection requires ad-blocking solutions, endpoint protection, regular patching, and ongoing employee awareness training.

Additional Reading:

CyberHoot does have some other resources available for your use. Below are links to all of our resources, feel free to check them out whenever you like: