When Trust Backfires: Malicious CDN Injects JavaScript Exploits into 100,000+ Websites
A malicious Content Delivery Network (CDN) was recently discovered distributing JavaScript exploits across more than 100,000 websites. The attacker managed to inject harmful scripts into seemingly legitimate JavaScript libraries hosted on the compromised CDN.
Since many developers blindly trust third-party CDNs for performance and convenience, the exploit propagated quickly and widely. The injected scripts could steal cookies, log keystrokes, or even redirect users to phishing sites without the site owner’s knowledge.
What makes this attack especially dangerous is its stealth — affected websites looked and functioned normally, hiding the malicious behavior in the background. This incident highlights the massive risk of relying on external scripts without verification or integrity checks. Many of the compromised websites were unaware anything was wrong until users or security researchers flagged suspicious activity.
Browser-level defenses like CSP (Content Security Policy) could have helped, but few sites had strong policies in place. The attack underlines the need for stronger supply chain security in web development. Ultimately, this is a wake-up call for developers to audit their dependencies — even the ones hosted by popular CDNs.
