China-linked hackers exploit Barracuda ESG zero-day vulnerability to breach public and private networks.

Chinese state-backed hackers used a security vulnerability in Barracuda Networks' Email Security Gateway to breach hundreds of public and private sector organizations globally, including nearly a third of government agencies, according to cybersecurity firm Mandiant. The hackers sent emails containing malicious file attachments to gain access to targeted organizations’ devices and data. Mandiant said the majority of the impact was in the Americas, reflecting the geography of Barracuda's customer base. Barracuda is providing replacement appliances to affected customers at no cost.