File-Squatting Exploitation by Example
This will (hopefully) be a short story about a bug I found some time ago while auditing a .NET service from an OEM. It should be interesting as I have yet to find a description of how to exploit a similar condition. Our service was running as SYSTEM and needed to periodically execute some other utilities as part of its workflow. Before running these auxiliary tools, it would check if the executable was properly signed by the vendor. Something like this: public void CallAgent() { string ExeFile = “C:\\Program…
Privilege Escalation Vulnerabilities Found in Lenovo System Update
Lenovo released a new version of the Lenovo System Update advisory (https://support.lenovo.com/ar/es/product_security/lsu_privilege) about two new privilege escalation vulnerabilities I had reported to Lenovo a couple of weeks ago (CVE-2015-8109, CVE-2015-8110). IOActive and Lenovo have issued advisories on these issues. Before digging into the details, let’s go over a high-level overview of how the Lenovo System Update pops up the GUI application with Administrator privileges. Here is a discussion of the steps depicted above: 1 – The user starts System Update…