ESET researchers have revealed that the Winter Vivern Russian hacking group has exploited a zero-day vulnerability in Roundcube Webmail, targeting various European government entities and think tanks.

ESET Research has been closely tracking the cyberespionage operations of Winter Vivern for more than a year and, during our routine monitoring, we found that the group began exploiting a zero-day XSS ...

This week, ESET research described how the Winter Vivern APT group has been exploiting a zero-day XSS vulnerability in Roundcube Webmail servers to target European governmental entities and a think ...

The Winter Vivern Russian hacking group has been exploiting a Roundcube Webmail zero-day in attacks targeting European government entities and think tanks since at least October 11. The Roundcube ...

A Russian cyberespionage group has been observed exploiting vulnerable Roundcube webmail servers in attacks against European government, military, and critical infrastructure entities, cybersecurity ...

Unknown threat actors have been observed attempting to exploit a now-patched security flaw in the open-source Roundcube webmail software as part of a phishing attack designed to steal user credentials ...

Attackers can exploit several vulnerabilities in Roundcube Webmail and, in the worst case, view emails from victims or even send them in their name. One vulnerability is classified as"critical".

Roundcube vulnerabilities refer to security flaws within the software that can be exploited by attackers to compromise the system. These vulnerabilities can lead to the software crashing or running ...

A code-smuggling gap in the Roundcube webmailer is already under attack. Tens of thousands of systems worldwide are still vulnerable. The critical security vulnerability in Roundcube Webmail that ...

Over 84,000 Roundcube webmail installations are vulnerable to CVE-2025-49113, a critical remote code execution (RCE) flaw with a public exploit. The flaw, which impacts Roundcube versions 1.1.0 ...