Cisco Duo Third-Party Compromise
On April 16, 2024, Cisco Duo informed affected customers of a breach involving their SMS and VOIP multi-factor authentication (MFA) service provider. The breach occurred on April 1st due to a phishing attack, allowing unauthorized access to the provider’s systems, including SMS and VoIP MFA message logs for specific Duo accounts between March 1st and March 31st, 2024. Though the threat actor accessed message logs, they did not obtain message content.