This can occur if the /dev/null device file has become corrupted or if access to /dev has been restricted.
Perform the following actions to troubleshoot /dev and /dev/null:
Check the contents of /dev/null
cat /dev/null
It should be empty, but if it returns data it could be an indication that someone or something copied a file in place of /dev/null instead of piping data out to /dev/null
Verify /dev/null file properties
ls -l /dev/null
Output should be as follows:
crw-rw-rw- 1 root root 1, 3 Apr 18 01:34 /dev/null
Verify /dev permissions
ls -dl dev
Output should be as follows:
drwxr-xr-x 19 root root 3180 Aug 23 10:26 dev