While responding to an incident at one of their clients, the PT ESC CSIRT team discovered a previously unknown backdoor written in Go, which they attributed to a cybercrime gang dubbed ExCobalt.
ExCobalt focuses on cyberespionage and includes several members active since at least 2016 and presumably once part of the notorious Cobalt gang. Cobalt attacked financial institutions to steal funds. One of Cobalt’s hallmarks was the use of the CobInt tool, something ExCobalt began to use in 2022. Over the past year, the PT ESC has recorded attacks linked to ExCobalt and investigated related incidents at Russian organizations in the following sectors: Metallurgy, Telecommunications, Mining, Information technology, Government, Software development
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Source: Positive Technologies
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