UserAgent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Firefox/60.0

Steps to reproduce the problem:
Hi Team, 

https://github.com/chromium/chromium/blob/master/base/base_paths_posix.cc#L63

i.e

if (realpath(getexecname(), bin_dir) == NULL) {

This function does not protect against buffer overflows, and some implementations can overflow internally such as (CWE-120/CWE-785!). 

Ensure that the destination buffer is at least of size MAXPATHLEN, andto protect against implementation problems, the input argument should also be checked to ensure it is no larger than MAXPATHLEN.

Request team to please have a look and validate.

Thank you

What is the expected behavior?

What went wrong?
Usages of realpath() are subject to bufferoverflows()

Did this work before? N/A 

Chrome version: 69.0.3473.1  Channel: stable
OS Version: 10.0
Flash Version: