oss-sec mailing list archives
Re: ldd can execute an app unexpectedly
From: Steve Grubb <sgrubb () redhat com>
Date: Mon, 7 Mar 2011 19:32:59 -0500
On Monday, March 07, 2011 07:00:11 pm Dmitry V. Levin wrote:
On Mon, Mar 07, 2011 at 06:27:05PM -0500, Steve Grubb wrote: [...]http://reverse.lostrealm.com/protect/ldd.html http://www.catonmat.net/blog/ldd-arbitrary-code-execution/ Besides telling everyone don't do that. ldd could take the PoV that it should only call runtime linkers in trusted directories like /sbin or /usr/sbin. Or it could simply detect that another linker was requested and make you add a "--force" so that you are fully aware that you just let another linker run. (The suggested patch can certainly be improved. But its here just in case you want it.)In June of 2002, I suggested to change ldd to avoid invoking programs directly, even when it seems like that would work, and invoke the dynamic linker as a program instead. This change was implemented at least in Owl and ALT Linux: http://cvsweb.openwall.com/cgi/cvsweb.cgi/~checkout~/Owl/packages/glibc/gli bc-2.3.6-owl-alt-ldd.diff http://git.altlinux.org/gears/g/glibc.git?p=glibc.git;a=commitdiff;h=78857 7027d2950e9508a434475e04c3af864d169
To be clear, I in no way want credit for this. Its been known for a long time. But if requirements have been loosened for CVEs, this is something people want to know about and probably patch. I strongly believe that it should be fixed. Any other skeletons in the closet that never got a CVE? -Steve
Current thread:
- ldd can execute an app unexpectedly Steve Grubb (Mar 07)
- Re: ldd can execute an app unexpectedly Dmitry V. Levin (Mar 07)
- Re: ldd can execute an app unexpectedly Steve Grubb (Mar 07)
- Re: ldd can execute an app unexpectedly Tim Brown (Mar 07)
- Re: ldd can execute an app unexpectedly Tomas Hoger (Mar 08)
- Re: ldd can execute an app unexpectedly Steve Grubb (Mar 08)
- Re: ldd can execute an app unexpectedly Dmitry V. Levin (Mar 07)