Bugtraq mailing list archives
Re: /proc filesystem allows bypassing directory permissions on Linux
From: Marco Verschuur <marco () osp nl>
Date: Tue, 27 Oct 2009 07:50:28 +0100
Why not?!? File permissions allow everybody write access to the file.The path via /proc to the file has been created when the initial path via /tmp was wide open.
Closing the initial path via /tmp has no effect on the /proc pathAnd due to the actual file permissions the read-only fd can easily changed to read-write.
Marco Sent from my iPhone 3G(s) On 26 okt 2009, at 22:58, psz () maths usyd edu au wrote:
Dear Casper and Dan,If you can control<pid>, then clearly you have access the file anyway simply by controlling it using a debugger.Sorry, but no. The "attacker" has the file opened O_RDONLY, and cannot "upgrade" that to O_RDWR. Cheers, Paul Paul Szabo psz () maths usyd edu au http://www.maths.usyd.edu.au/u/psz/School of Mathematics and Statistics University of Sydney Australia
Current thread:
- Re: /proc filesystem allows bypassing directory permissions on Linux, (continued)
- Re: /proc filesystem allows bypassing directory permissions on Linux Pavel Machek (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Dan Yefimov (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Pavel Machek (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Dan Yefimov (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Tamber Penketh (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Pavel Machek (Oct 27)
- Re: /proc filesystem allows bypassing directory permissions on Linux Glynn Clements (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Casper . Dik (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Dan Yefimov (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux psz (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Marco Verschuur (Oct 27)
- Re: /proc filesystem allows bypassing directory permissions on Linux psz (Oct 27)
- Re: /proc filesystem allows bypassing directory permissions on Linux Marco Verschuur (Oct 28)
- Re: /proc filesystem allows bypassing directory permissions on Linux Pavel Machek (Oct 29)
- Re: /proc filesystem allows bypassing directory permissions on Martin Rex (Oct 29)
- Re: /proc filesystem allows bypassing directory permissions on Pavel Machek (Oct 30)
- Re: /proc filesystem allows bypassing directory permissions on Linux Anton Ivanov (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Dan Yefimov (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Anton Ivanov (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Dan Yefimov (Oct 26)
- Re: /proc filesystem allows bypassing directory permissions on Linux Anton Ivanov (Oct 26)