# Anyone knows this warning? **URL:** \ **Category:** Ruby\ **Created:** [January 6, 2009, 9:08am UTC](https://www.ruby-forum.com/t/anyone-knows-this-warning/156989 "2009-01-06T09:08:26Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![youhaodeyi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/b9bd4f/32.png) [@youhaodeyi](https://www.ruby-forum.com/u/youhaodeyi)\ **Post date:** [January 6, 2009, 9:08am UTC](https://www.ruby-forum.com/t/anyone-knows-this-warning/156989/1 "2009-01-06T09:08:26Z")
When my ruby runs an external program, it will get this warning: warning: Insecure world writable dir SOMEDIR I have checked the SOMEDIR and its permission mode is 777. Does anyone know this warning? How can I avoid this? thanks ---
**Author:** ![youhaodeyi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/b9bd4f/32.png) [@youhaodeyi](https://www.ruby-forum.com/u/youhaodeyi)\ **Post date:** [January 6, 2009, 10:02am UTC](https://www.ruby-forum.com/t/anyone-knows-this-warning/156989/2 "2009-01-06T10:02:31Z")
Zhao Yi wrote: > When my ruby runs an external program, it will get this warning: > warning: Insecure world writable dir SOMEDIR > > I have checked the SOMEDIR and its permission mode is 777. Which means it’s world-writable, as the warning says. In octal: ``` 7 7 7 ``` 111 111 111 rwx rwx rwx (user, group, world) The warning comes from path\_check\_0 in file.c, which in turn is called from rb\_path\_check, which checks each of the directories in your PATH. It’s basically saying: when you do system(“foo”), one of your PATH directories is world writable, so any random user on your system could have installed their own “foo” executable which does whatever they like (e.g. changing your password, or mailing your pr0n collection to your girlfriend 🙂 > How can I avoid this? man chmod ---
**Author:** ![youhaodeyi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/b9bd4f/32.png) [@youhaodeyi](https://www.ruby-forum.com/u/youhaodeyi)\ **Post date:** [January 6, 2009, 10:27am UTC](https://www.ruby-forum.com/t/anyone-knows-this-warning/156989/3 "2009-01-06T10:27:47Z")
Zhao Yi wrote: > why does ruby check its permission? Because not heeding this warning is approximately the same as posting your password in clear text to all users on the system. Even if you have no other users on your system, if someone happens to break in (e.g. through your web server or mail server), and gets a shell running as any daemon user, they can exploit this hole to run any script as _your_ userid. > I do want this path writable. how > can I disable this warning? I already pointed you at file.c. You will find a #if check in there, which lets you recompile ruby with this check disabled. I’m not going to hint further. If you are smart enough to understand fully the consequences of disabling this check, then you a smart enough to read the configure script and recompile ruby with this check disabled. ---
**Author:** ![youhaodeyi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/b9bd4f/32.png) [@youhaodeyi](https://www.ruby-forum.com/u/youhaodeyi)\ **Post date:** [January 6, 2009, 10:10am UTC](https://www.ruby-forum.com/t/anyone-knows-this-warning/156989/4 "2009-01-06T10:10:59Z")
Brian C. wrote: > Which means it’s world-writable, as the warning says. In octal: > > ``` > 7 7 7 > > ``` > > 111 111 111 > rwx rwx rwx (user, group, world) > > man chmod why does ruby check its permission? I do want this path writable. how can I disable this warning? ---
**Author:** ![youhaodeyi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/b9bd4f/32.png) [@youhaodeyi](https://www.ruby-forum.com/u/youhaodeyi)\ **Post date:** [January 7, 2009, 5:11am UTC](https://www.ruby-forum.com/t/anyone-knows-this-warning/156989/5 "2009-01-07T05:11:24Z")
On Tue 6.Jan’09 at 18:14:05 +0900, Zhao Yi wrote: > why does ruby check its permission? > Why not? Ruby is letting you know that something bad can happen. > I do want this path writable. how can I disable this warning? ruby -W0 /path/to/your\_script -drd ---
**Author:** ![youhaodeyi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/b9bd4f/32.png) [@youhaodeyi](https://www.ruby-forum.com/u/youhaodeyi)\ **Post date:** [January 7, 2009, 6:47am UTC](https://www.ruby-forum.com/t/anyone-knows-this-warning/156989/6 "2009-01-07T06:47:17Z")
Zhao Yi wrote: > When my ruby runs an external program, it will get this warning: > warning: Insecure world writable dir SOMEDIR > > I have checked the SOMEDIR and its permission mode is 777. Does anyone > know this warning? How can I avoid this? > > thanks World read, write and execute is a bad thing if you’re on a shared server with other users. Any good system will error and prevent it from running, instead of blindling running it. Else you risk issues where another user on the system can write to your files/directories, destroy, modify or delete your valuable data, as well as open exploitable potentials. If this is your own server and you don’t share it with any other users (or other users you can’t trust), then you can remove that check if you wish. Still, even when running with a lower privileged user instead of your own for better protection (if you run insecure scripts or you aren’t able to ensure they are secure), it still shouldn’t need world write/execute. ---
**Author:** ![youhaodeyi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/b9bd4f/32.png) [@youhaodeyi](https://www.ruby-forum.com/u/youhaodeyi)\ **Post date:** [January 7, 2009, 2:57pm UTC](https://www.ruby-forum.com/t/anyone-knows-this-warning/156989/7 "2009-01-07T14:57:37Z")
Zhao Yi wrote: > When my ruby runs an external program, it will get this warning: > warning: Insecure world writable dir SOMEDIR > > I have checked the SOMEDIR and its permission mode is 777. Does anyone > know this warning? How can I avoid this? > > thanks I understand that you want this directory to be world-writable, so this is probably not much use for your current situation, but handy to know nonetheless. You may want to configure a group, see /etc/groups, man groups, or man chgrp instead of having it be world-writable. With that aside, there are two ways to modify the permissions for files and directories. In essence, it’s by name or by number. Using the names is better when beginning. See man chmod for more details. Basically, you can use the syntax ‘chmod \\<+ or -\>\’. \ would be one of the following {a,u,g,o} where a is all (user group and other), u is user, g is group, and o is other (typically everyone else). \<+ or -\> is a boolean true or false for turning on or off the permission. \ would be {r,w,x} where r is read, w is write, and x is execute. So for example, if you wanted to remove the read ability for everyone except the user and group, you would use: chmod o-r test-file.txt You can group them as well, so the following is valid for adding write ability for the user and group: chmod ug+r test-file.txt The a for access level is a shortcut for all three. So to remove all types ability to execute a file: chmod a-x test-file.txt Also, you will probably want to check into man chown for how to change the user attribute for a specific file or set. Hope that helps. Best regards, Ryan Masters End Point Corp. removed\_email\_address@domain.invalid