Winter Vivern APT Blasts Webmail Zero-Day Bug With One-Click Exploit

October 25, 2023 at 11:41AM Winter Vivern, a low-profile threat group, has been exploiting a zero-day flaw in Roundcube Webmail servers to target governmental organizations and a think tank in Europe. The group sends a specially crafted email that loads an arbitrary JavaScript code, exploiting a newly discovered cross-site scripting flaw. Roundcube has released security … Read more