Hi, I can't reach the Documentation Project Tutorial site suggested as the best place to start, since it doesn't like the fact that my proxy strips user-agent headers- so I hope I'm not jumping out of line here...
It's been known for quite some time that the default configuration with UserDir enabled lets people scan for user-ids because a valid ID returns a 403 if there's no public_html, while an invalid one returns a 404- it's been years since it was seriously discussed, however a new "script kiddie friendly" tool is out now which exploits that in conjunction with FTP and same ID/password combos to compromise servers. IOW: a get for /~hidden will return a 403, where a get for /~nonexistent will return a 404- so an attacker can enumerate users on a server by running a dictionary word list through, and ignoring any hits that 404. Given that, I'd like to see a section added to "Security Tips" about UserDir, along the lines of: ========== begin =========== If your server doesn't have users who need to have ~username directories accessible, you should substitute the default "UserDir public_html" statement in the httpd configuration file with UserDir disabled. If you require UserDir to be enabled, then you might consider either using the ErrorDocument directive to make the 403 and 404 errors serve up the same custom response, or limiting which accounts can have UserDirs with something like: UserDir disabled UserDir enabled probertson test foo UserDir public_html This will stop Apache from disclosing which user-ids exist on a system, which attackers may use to figure out hidden, administrative or temporary ids which might be exploited by other non-Apache attack vectors, such as FTP or SSH. =========end========== I can add a diff if someone can point me at an accessible document that tells me what original files need to be changed and in what format, or if someone who can easily submit the changes wants to do that, that'll work too. If it's not an appropriate change, I'd appreciate some feedback on that too. This information is applicable to both the 1.3 and 2.x trees. Thanks, Paul -------------------------------------------------------------------- Paul D. Robertson Director of Risk Assessment, TruSecure Corporation Moderator, Firewall-Wizards http://honor.icsalabs.com/ [EMAIL PROTECTED] *********************************************************************** This message is intended only for the use of the intended recipient and may contain information that is PRIVILEGED and/or CONFIDENTIAL. If you are not the intended recipient, you are hereby notified that any use, dissemination, disclosure or copying of this communication is strictly prohibited. If you have received this communication in error, please destroy all copies of this message and its attachments and notify us immediately. *********************************************************************** --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
