The provided information describes a malspam campaign dated June 22, 2016, involving the distribution of the Locky ransomware via malicious JavaScript (.js) files compressed inside ZIP archives. Locky is a well-known ransomware family that encrypts victims' files and demands ransom payments for decryption keys. In this campaign, attackers used email spam to deliver ZIP attachments containing JavaScript files. When executed, these scripts download and install the Locky ransomware onto the victim's system. This infection vector leverages social engineering to trick users into opening the ZIP file and executing the embedded JavaScript, often by disguising the attachment as an invoice or other business-related document. The campaign is classified as malware with a low severity rating by the source, and no known exploits in the wild are reported beyond the malspam distribution itself. The threat level is indicated as 3 (on an unspecified scale), and no specific affected software versions or patches are listed. The lack of CVSS score and limited technical details suggest this is a known but relatively low-impact campaign compared to more sophisticated or widespread ransomware outbreaks.

For European organizations, the impact of this Locky malspam campaign primarily involves potential data encryption leading to operational disruption and financial loss. If users execute the malicious JavaScript, their systems could become infected with ransomware, resulting in encrypted files and potential downtime. This can affect confidentiality if sensitive data is exfiltrated prior to encryption, integrity due to file modification, and availability as encrypted data becomes inaccessible. Although the campaign is rated low severity, organizations with insufficient email filtering, user awareness, or endpoint protection could be vulnerable. The impact is exacerbated in sectors reliant on continuous data availability, such as healthcare, finance, and critical infrastructure. Additionally, ransom payments may lead to financial losses and encourage further attacks. However, the absence of known exploits in the wild beyond the malspam vector and the dated nature of the campaign suggest that modern defenses and updated user training can effectively mitigate this threat.

To mitigate this threat, European organizations should implement multi-layered defenses focused on email security and endpoint protection. Specifically: 1) Deploy advanced email filtering solutions that scan and block suspicious ZIP attachments and JavaScript files, including sandboxing to detect malicious behavior. 2) Enforce strict attachment policies that block or quarantine executable scripts received via email. 3) Conduct regular user awareness training emphasizing the risks of opening unexpected attachments, especially ZIP files containing scripts. 4) Maintain up-to-date endpoint protection platforms with behavioral detection capabilities to identify and block ransomware execution. 5) Implement application whitelisting to prevent unauthorized script execution. 6) Regularly back up critical data offline or in immutable storage to enable recovery without paying ransom. 7) Monitor network traffic for indicators of compromise related to Locky ransomware communications. 8) Apply network segmentation to limit ransomware spread if infection occurs. These measures go beyond generic advice by focusing on script-based attachment filtering, user education specific to ZIP/JS threats, and proactive detection strategies.