RowHammer and Beyond

  • Onur MutluEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11421)


We will discuss the RowHammer problem in DRAM, which is a prime (and likely the first) example of how a circuit-level failure mechanism in Dynamic Random Access Memory (DRAM) can cause a practical and widespread system security vulnerability. RowHammer is the phenomenon that repeatedly accessing a row in a modern DRAM chip predictably causes errors in physically-adjacent rows. It is caused by a hardware failure mechanism called read disturb errors. Building on our initial fundamental work that appeared at ISCA 2014, Google Project Zero demonstrated that this hardware phenomenon can be exploited by user-level programs to gain kernel privileges. Many other recent works demonstrated other attacks exploiting RowHammer, including remote takeover of a server vulnerable to RowHammer. We will analyze the root causes of the problem and examine solution directions. We will also discuss what other problems may be lurking in DRAM and other types of memories, e.g., NAND flash and Phase Change Memory, which can potentially threaten the foundations of reliable and secure systems, as the memory technologies scale to higher densities.



This short paper and the associated keynote talk are heavily based on two previous papers we have written on RowHammer, one that first introduced the phenomenon in ISCA 2014 [55] and the other that provides an analysis and future outlook on RowHammer [80]. They are a result of the research done together with many students and collaborators over the course of the past 7–8 years. In particular, three PhD theses have shaped the understanding that led to this work. These are Yoongu Kim’s thesis entitled “Architectural Techniques to Enhance DRAM Scaling” [54], Yu Cai’s thesis entitled “NAND Flash Memory: Characterization, Analysis, Modeling and Mechanisms” [24] and his continued follow-on work after his thesis, summarized in [27, 28], and Donghyuk Lee’s thesis entitled “Reducing DRAM Latency at Low Cost by Exploiting Heterogeneity” [62]. We also acknowledge various funding agencies (NSF, SRC, ISTC, CyLab) and industrial partners (AliBaba, AMD, Google, Facebook, HP Labs, Huawei, IBM, Intel, Microsoft, Nvidia, Oracle, Qualcomm, Rambus, Samsung, Seagate, VMware) who have supported the presented and other related work in my group generously over the years. The first version of this talk was delivered at a CMU CyLab Partners Conference in September 2015. Another version of the talk was delivered as part of an Invited Session at DAC 2016, with a collaborative accompanying paper entitled “Who Is the Major Threat to Tomorrow’s Security? You, the Hardware Designer” [16]. The most recent version is the invited talk given at the Top Picks in Hardware and Embedded Security workshop, co-located with ICCAD 2018 [7], where RowHammer was selected as a Top Pick among hardware and embedded security papers published between 2012–2017. I would like to also thank Christina Giannoula for her help in preparing this manuscript.


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.ETH ZürichZürichSwitzerland
  2. 2.Carnegie Mellon UniversityPittsburghUSA

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