Brevo Supply Chain Attack Injects Malware Into 100,000 Websites

As cited

Copy frozen at 2026-09-18 13:01 UTC (site build).

breaches incidents

Brevo Supply Chain Attack Injects Malware Into 100,000 Websites

Attackers compromised an application programming interface (API) key and deployed a malicious Cloudflare worker to inject scripts across approximately 100,000 websites through Brevo, a marketing platform. The supply chain attack leveraged trusted infrastructure to distribute malware at scale.

Why it matters: Website operators and Brevo customers face potential credential theft, malware distribution, and defacement; practitioners should audit API key permissions, review Cloudflare worker deployments, and check their sites for injected scripts immediately.

Source published

2026-09-18 09:46 UTC

First seen by Cybersecurity Tracker

2026-09-18 11:23 UTC