mediaserver in Android 4.x before 4.4.4, 5.0.x before 5.0.2, 5.1.x before 5.1.1, and 6.x before 2016-06-01 does not validate OMX buffer sizes, which allows attackers to gain privileges via a crafted application, as demonstrated by obtaining Signature or SignatureOrSystem access, aka internal bug 27207275.
https://android.googlesource.com/platform/frameworks/av/+/db829699d3293f254a7387894303451a91278986
https://android.googlesource.com/platform/frameworks/av/+/94d9e646454f6246bf823b6897bd6aea5f08eda3
https://android.googlesource.com/platform/frameworks/av/+/295c883fe3105b19bcd0f9e07d54c6b589fc5bff
https://android.googlesource.com/platform/frameworks/av/+/0bb5ced60304da7f61478ffd359e7ba65d72f181