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+++ This bug was initially created as a clone of Bug #1418824 +++

In polkit-112-9.el7 pkexec.c is a memory leak that can be used to "spray the heap". Compare https://googleprojectzero.blogspot.nl/2014/08/the-poisoned-nul-byte-2014-edition.html "Step 5: Aha! use a command-line argument spray to effect a heap spray and collide the heap into the stack". The article describes an effective attack using this ability to "heap spray".

This issue has been fixed upstream by disallowing multiple user invocations:

https://cgit.freedesktop.org/polkit/commit/src/programs/pkexec.c?id=6c992bc8aefa195a41eaa41c07f46f17de18e25c

Similar issues exist in pkcheck.c but since that binary is not setuid the memory leaks in that binary are not quite as acute. Compare bug #1418278 & bug #1418287 .

After evaluating this issue, there are no plans to address it further or fix it in an upcoming release.  Therefore, it is being closed.  If plans change such that this issue will be fixed in an upcoming release, then the bug can be reopened.