When I first spoke to Drake a year ago, he explained to me that the Stagefright issues were in large part integer overflows that lead to potentially exploitable memory buffer overflow conditions. The danger was that hundreds of millions of Android users were at risk from the issue, and unfortunately, a year later, hundreds of millions of Android users remain at risk.
The initial set of Stagefright vulnerabilities were publicly disclosed at Black Hat USA 2015 and led Google to rethink its process for Android security, ushering in a new monthly cycle for Android patch updates. As it turns out, the initial Stagefright issues Drake disclosed were not the last libstagefright flaws, and he wasn’t the only security researcher to find stagefright-related flaws.