Row hammer (also written as rowhammer) is an unintended side effect in dynamic random-access memory (DRAM) that causes memory cells to leak their charges and interact electrically between themselves, possibly altering the content of nearby memory rows that actually were not addressed in the original memory access. This circumvention of the DRAM memory cells isolation results from the high cell density in modern DRAM, and can be triggered by specially crafted memory access patterns that rapidly activate the same memory rows numerous times. The row hammer effect has been used in some privileg...