/tmp/swap is causing my CPU busy

[Warren Block]

On Tue, 10 Jan 2017, Bill Yuan wrote:

> Hi,
> Need support here. I just noticed my machine is busy and a process is the
> root cause, I am not familiar with the memory/SWAP, Can someone please help
> to take a look? any info is required? please let me know.
>
> #top
> 52 processes:  1 running, 50 sleeping, 1 zombie
> CPU:  3.5% user,  0.0% nice,  0.6% system,  0.0% interrupt, 95.9% idle
> Mem: 53M Active, 997M Inact, 133M Wired, 44M Buf, 791M Free
> Swap: 2100M Total, 2100M Free
>
>  PID USERNAME       THR PRI NICE   SIZE    RES STATE   C   TIME    WCPU
> COMMAND
> 25592 root            10  25    0   778M  9272K uwait   3   0:38  19.02%
> .swap
> 25599 root             1  20    0  7416K  2596K CPU0    0   0:00   0.11% top
>
> #ps -axd | grep swap
> 25481  0  S+       0:00.00 | |   `-- grep swap
> 22927  -  Ss     172:10.74 |-- /tmp/.swap
>
> #uname -a
> FreeBSD NetGate1 11.0-RELEASE-p1 FreeBSD 11.0-RELEASE-p1 #0 r306420: Thu
> Sep 29 03:40:55 UTC 2016
> root at releng2.nyi.freebsd.org:/usr/obj/usr/src/sys/GENERIC
> i386

That does not look good to me.  A hidden file named ".swap" that is 
*running*, and as root?  I would immediately disconnect that machine 
from the net and then check to see if that's a compromise, because it 
sure looks fishy.