To begin,this is a vulnerability that I found during a bug bounty engagement.I would split this into two parts, or two separate vulnerabilities. The First part was a web cache poisoning via X Headers.This part allowed me to achieve XSS on every endpoint with a combination of two Headers.The next part was a OAuth flow flaw that allowed me to leverage my previously given XSS capabilities into an account takeover through a technique I call cookie overriding.Before …

Back in 2018, a group of security researchers and I decided to try our hands at OpenEMR and find security vulnerabilities.The full report can be found here.This a very good read and I recommend reading it in its entirety. However this blog post is just documenting my contribution to the project.The following are the three CVEs I received in the collaboration. These were all responsibly disclosed and patched so upgrading to the latest version would be well advised.

1.CVE-2018–15140-Authenicated Arbitrary Read

Vulnerable Code:

if ($_POST['mode'] == 'get'){
echo file_get_contents($_POST['docid']);

This is a vulnerability that allows an attacker to…

Josh Fam

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