Qualys Is the Latest Victim of Accellion Data Breach Security vendor confirms attackers exploited a previously disclosed vulnerability in the enterprise firewall technology to breach its network. Qualys has become the latest known victim of a data breach at enterprise firewall vendor Accellion that has affected numerous companies including, most notably, retail giant Kroger, law firm Jones Day, and the state of Washington. In a statement late Wednesday, Qualys confirmed rumors that had been circulating all day about the company's network having been breached. But it provided few details on the nature of the incident or whether it had become a victim of the Clop ransomware strain, as numerous people reported via Twitter on Wednesday.