Menlo Labs has been tracking a malicious email campaign targeting employees of banks and financial services companies. The campaign, which appears to have been active in the U.S. and the UK since August, compromises PCs and other endpoints by tricking victims into clicking on malicious links to archive files. In all of the instances we’ve identified so far in this particular campaign, the archive files were either .zip or .gz files.

https://www.menlosecurity.com/blog/a-jar-full-of-problems-for-financial-services-companies