Tried chkrootkit and it listed a few temporarily files from previous kernel updates. As mentioned in this link. I guess it's a false positive then.
output chkrootkit:
link
Searching for suspicious files and dirs, it may take a while... The following suspicious files and directories were found:
/usr/lib/debug/.build-id /usr/lib/modules/5.4.0-47-generic/vdso/.build-id /usr/lib/modules/5.4.0-48-generic/vdso/.build-id
/usr/lib/debug/.build-id /usr/lib/modules/5.4.0-47-generic/vdso/.build-id /usr/lib/modules/5.4.0-48-generic/vdso/.build-id
Tried to remove the older kernels, but hav not found the correct shell command for it, so far nothing works. Maybe I will just leave it as it is....
Switched to duckduckgo search engine