Title. Long,short story: creating or editing files with nano as my non-root user gives (the file) elevated privileges, like I have ran it w/ sudo or as root. And the (only) “security hole” that I can think of is a nextdns docker container running as root. That aside, its very “overkill” security-wise (cap_drop=ALL, non-root image, security_opt=no_new_privileges, etc.).
It’s like someone tried to hack me but gave up halfway. Am I right or wrong to assume this? Just curious.
Thanks in advance.
Do you run docker container in privileged mode? https://phoenixnap.com/kb/docker-privileged
And do you run nano inside the container?
Docker container running in privileged mode has root permissions to host filesystem and devices (limited by said restrictions).
What are the permissions on the directory the file resides in?
I already talked about it in this thread – it shows my sudoer username on both columns.
Show the full output of
ls -ld directory(replace “directory” with real directory path).
Can you be more specific about what you mean by this: “gives (the file) elevated privileges”?
i.e file is created (as non-root), trying to remove the file (once again, as non-root) gives me a “
rm: cannot remove 'dir/file.name': Permission denied” error message.OK I see. Can you create a new file with nano and then do an “ls -l” so we can see the permissions it’s given? Also provide the output of the command “umask” as the user you’re working with.
Just did it, and it shows my sudoer username with ownership of the created file.
umaskreturns me 0002.Can you paste the line from ls -l? Sanitize the username/date/time if you need to. Example:
-rw-r–r-- 1 bolapara users 0 Nov 21 17:19 asdf
-rw-rw-r-- 1 $sudoer $sudoer $date $createdfilename.That is not an elevated permission, your user should be able to delete that file, do the same in another directory if it works it might be a permission, or more likely an attribute, problem on the directory itself or something on the path to it.
You cannot say if user able do delete the file or not. It depends on the directory permissions (deleting a file is modifying a directory).
What are the permissions on the directory? What is command are you running to edit the file? What command are you running to delete it? (Have you got selinux turned on? What filesystem is this directory on?)
Do you have write permissions on the directory?
The directory you are creating your files in likely is set to immutable or append only.
lsattr -d /path/to/directory
if you see i or a, then that’s the issue.
You can remove them with
sudo chattr -i /path/to/dir #removes immutable
sudo chattr -a /path/to/dir #removes append onlySame goes for files but if it happens to all files in a directory, then that is probably it.
