In some cases, the backdoor has been unable to work as intended. The build environment on Fedora 40, for example, contains incompatibilities that prevent the injection from correctly occurring.
It’s really funny that it’s package incompatibilites that saved us.
There’s a joke that I can’t find now about how hard it is to install a virus in Linux even if you try.
Downloaded a virus for Linux lately and unpacked it.
Tried to run as root, didn’t work.
Googled for 2 hours, found out that instead of /usr/local/bin the virus unpacked to /usr/bin for which the user malware doesn’t have any write permissions, therefore the virus couldn’t create a process file.
Found patched .configure and .make files on some Chinese forum, recompiled and rerun it.
The virus said it needs the library cmalw-lib-2.0. Turns out cmalw-lib-2.0 is shipped with CentOS but not with Ubuntu. Googled for hours again and found an instruction to build a .deb package from source.
The virus finally started, wrote some logs, made a core dump and crashed. After 1 hour of going through the logs I discovered the virus assumed it was running on ext4 and called into its disk encryption API. Under btrfs this API is deprecated. The kernel noticed and made this partition read-only.
Opened the sources, grep’ed the Bitcoin wallet and set $5 out of pity.
It’s really funny that it’s package incompatibilites that saved us.
There’s a joke that I can’t find now about how hard it is to install a virus in Linux even if you try.
That’s it! Thank you!
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