The Russian-linked hacker group Fancy Bear , also known as APT28 and Sednit, is targeting arms suppliers to Ukraine, including companies in Bulgaria , according to a report by the security firm ESET, writes Cyberscoop . The campaign, ongoing since 2023, employs vulnerabilities in webmail software like Roundcube, Horde, MDaemon, and Zimbra to access communications and emails of executives at arms firms and government officials in multiple countries. The latest detected attack was on April 17.