Russian-linked hackers, operating with interests aligned to Belarus and Russia, have been identified in a cyber espionage campaign targeting more than 80 organizations. The threat actor, known as Winter Vivern or TAG-70, exploited cross-site scripting (XSS) vulnerabilities in Roundcube webmail servers, focusing on entities primarily located in Georgia, Poland, and Ukraine. Recorded Future, the cybersecurity firm tracking the campaign, highlighted the sophistication of TAG-70’s attack methods, involving social engineering techniques and Roundcube flaws to gain unauthorized access to targeted mail servers.
Winter Vivern, active since at least December 2020, has previously exploited vulnerabilities in Zimbra Collaboration email software, displaying a pattern of sophisticated cyber activities. The recent campaign, occurring from October 2023, aimed at collecting intelligence on European political and military activities, demonstrating the threat actor’s persistent and strategic focus. TAG-70 utilized attack chains involving Roundcube flaws to deliver JavaScript payloads, exfiltrating user credentials to a command-and-control (C2) server.
Recorded Future uncovered evidence of TAG-70 targeting Iranian embassies in Russia and the Netherlands, along with the Georgian Embassy in Sweden. This suggests a broader geopolitical interest in assessing diplomatic activities, especially regarding Iran’s support for Russia in Ukraine. Additionally, espionage against Georgian government entities reflects an interest in monitoring Georgia’s aspirations for European Union (EU) and NATO accession. The findings underscore the ongoing sophistication and strategic objectives of Russian-linked threat actors in the cyber landscape.
