All Your PC Are Belong to Us: Exploiting Non-control-Transfer Instruction BTB Updates for Dynamic PC Extraction

Jiyong Yu, Trent Jaeger, Christopher W. Fletcher

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Scopus citations


Leaking a program’s instruction address (PC) pattern, completely and precisely, has long been a sought-after capability for microarchitectural side-channel attackers. Case in point, such a primitive would be sufficient to construct powerful control-flow leakage attacks (inferring program secrets impacting control flow) that defeat existing control-flow leakage mitigations, or even reverse-engineer private binaries through PC-trace granular fingerprinting. However, current side-channel attack techniques only capture PCs at a coarse granularity or for only specific instruction types. In this paper, we propose the first micro-architectural side-channel attack that is capable of directly observing the exact PCs of arbitrary victim dynamic instructions—i.e., even the PCs of non-control-transfer instructions and even if the program code is private. Our attack exploits several previously overlooked characteristics in modern Intel Branch Target Buffers (BTBs). The core observation is perhaps counter-intuitive: despite being a structure related to control-flow prediction, the BTB incurs observable state changes after the execution of potentially any instruction, not just control-transfer instructions. Through reverse-engineering and analyzing said BTB vulnerabilities, we design and implement an attack framework named NightVision. We demonstrate how NightVision is capable of efficiently and accurately identifying a subset, or the entirety, of a victim program’s dynamic PC trace (depending on the attacker’s capabilities). We show how NightVision enables a new control-flow attack that bypasses prior defenses. Additionally, we show that when combined with code fingerprinting techniques, NightVision enables reverse-engineering of private programs.

Original languageEnglish (US)
Title of host publicationISCA 2023 - Proceedings of the 2023 50th Annual International Symposium on Computer Architecture
PublisherInstitute of Electrical and Electronics Engineers Inc.
Number of pages14
ISBN (Electronic)9798400700958
StatePublished - Jun 17 2023
Event50th Annual International Symposium on Computer Architecture, ISCA 2023 - Orlando, United States
Duration: Jun 17 2023Jun 21 2023

Publication series

NameProceedings - International Symposium on Computer Architecture
ISSN (Print)1063-6897


Conference50th Annual International Symposium on Computer Architecture, ISCA 2023
Country/TerritoryUnited States

All Science Journal Classification (ASJC) codes

  • Hardware and Architecture

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