# Brevo Supply Chain Attack Compromises Customer Websites with Malicious Scripts

*Published September 18, 2026*
*Source: [https://www.bleepingcomputer.com/news/security/brevo-supply-chain-attack-injected-clickfix-scripts-on-customer-sites/](https://www.bleepingcomputer.com/news/security/brevo-supply-chain-attack-injected-clickfix-scripts-on-customer-sites/)*

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## Article

In a significant cybersecurity incident, attackers have exploited Brevo by stealing its Cloudflare API key. This breach allowed them to inject malicious JavaScript scripts, known as ClickFix, into various customer websites. The attack has impacted numerous businesses that rely on Brevo's services, putting both their websites and users at risk.

The breach was discovered when unusual activities were noticed on customer sites, leading to an investigation that traced the source back to the compromised API key. The attackers used this key to deliver harmful scripts, which could potentially compromise sensitive data or disrupt website functionality. The specifics of how the API key was compromised remain unclear, but the incident underscores the vulnerability of supply chain components.

Brevo has since taken measures to mitigate the attack, including revoking the compromised API key and working closely with affected customers to remove the malicious scripts. Customers are urged to review their security protocols and ensure that their systems are not further compromised.

This incident highlights the critical importance of securing third-party access and the potential risks associated with supply chain vulnerabilities. Businesses are encouraged to reassess their security strategies, particularly concerning their reliance on external services.