Date: Wed, 15 Apr 2015 13:44:45 -0700 From: Tavis Ormandy <taviso@...gle.com> To: oss-security@...ts.openwall.com Subject: Re: Re: Problems in automatic crash analysis frameworks On Wed, Apr 15, 2015 at 2:45 AM, Jakub Filak <jfilak@...hat.com> wrote: > Hello, > > I have a question regarding the ABRT vulnerabilities. I don't particularly understand how an attacker can use /proc/pid/exe symlink to force ABRT to read an arbitrary file if the symlink cannot be changed and kernel refuses to create the process if the symlink's target is not executable. > >> This code trusts the /proc/pid/exe symlink, even though it is possible >> to link it anywhere you want. >> >> https://github.com/abrt/abrt/blob/master/src/hooks/abrt-hook-ccpp.c#L368 >> >> sprintf(buf, "/proc/%lu/exe", (long)pid); >> int src_fd_binary = open(buf, O_RDONLY); /* might fail and >> return -1, it's ok */ > > Thank you for clarifying this for me. > My description was incorrect, It can't be an arbitrary file, just a file you have execute but not read permission. Tavis.
Powered by blists - more mailing lists
Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.