Pavel Machek wrote: >On Sat 2009-10-24 01:12:51, Dan Yefimov wrote: >> On 24.10.2009 0:35, Matthew Bergin wrote: >> >doesnt look like the original owner is trying to write to it. Shows it >> >cant, it had guest write to it via the proc folders bad permissions. >> >Looks legitimate >> > >> Please tell me, who issued 'chmod 0666 unwritable_file'? Was that an >> attacker? No, that was the owner of 'unwritable_file', nobody else. >> What the 0666 file mode means? It means, that everybody can write to >> the file, can't he? So why do you believe that pretension >> legitimate? > >Original owner did chmod 666... after making sure traditional unix >permissions protect the file. Please look at original mail; it was >subtle but I believe I got it right, and file would not be writable >with /proc unmounted.
In Solaris, you don't have permission to access a file in /proc/<pid>/fd unless you can control the process <pid>. $ ls -l /proc/1/fd /proc/1/fd: Permission denied If you can control <pid>, then clearly you have access the file anyway simply by controlling it using a debugger. I agree with Pavel's assessment here. Casper