Meltdown: Reading Kernel Memory from User Space
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Oracle VM Virtualbox User Manual
Oracle VM VirtualBox R User Manual Version 5.1.20 c 2004-2017 Oracle Corporation http://www.virtualbox.org Contents 1 First steps 11 1.1 Why is virtualization useful?............................. 12 1.2 Some terminology................................... 12 1.3 Features overview................................... 13 1.4 Supported host operating systems.......................... 15 1.5 Installing VirtualBox and extension packs...................... 16 1.6 Starting VirtualBox.................................. 17 1.7 Creating your first virtual machine......................... 18 1.8 Running your virtual machine............................ 21 1.8.1 Starting a new VM for the first time.................... 21 1.8.2 Capturing and releasing keyboard and mouse.............. 22 1.8.3 Typing special characters.......................... 23 1.8.4 Changing removable media......................... 24 1.8.5 Resizing the machine’s window...................... 24 1.8.6 Saving the state of the machine...................... 25 1.9 Using VM groups................................... 26 1.10 Snapshots....................................... 26 1.10.1 Taking, restoring and deleting snapshots................. 27 1.10.2 Snapshot contents.............................. 28 1.11 Virtual machine configuration............................ 29 1.12 Removing virtual machines.............................. 30 1.13 Cloning virtual machines............................... 30 1.14 Importing and exporting virtual machines..................... 31 1.15 Global Settings................................... -
Understanding Full Virtualization, Paravirtualization, and Hardware Assist
VMware Understanding Full Virtualization, Paravirtualization, and Hardware Assist Contents Introduction .................................................................................................................1 Overview of x86 Virtualization..................................................................................2 CPU Virtualization .......................................................................................................3 The Challenges of x86 Hardware Virtualization ...........................................................................................................3 Technique 1 - Full Virtualization using Binary Translation......................................................................................4 Technique 2 - OS Assisted Virtualization or Paravirtualization.............................................................................5 Technique 3 - Hardware Assisted Virtualization ..........................................................................................................6 Memory Virtualization................................................................................................6 Device and I/O Virtualization.....................................................................................7 Summarizing the Current State of x86 Virtualization Techniques......................8 Full Virtualization with Binary Translation is the Most Established Technology Today..........................8 Hardware Assist is the Future of Virtualization, but the Real Gains Have -
Privacy and Security
Privacy and Security Sekar Kulandaivel, Jennifer Xiao - April 21, 2020 Understanding Contention-Based Channels and Using Them for Agenda Defense Spectre Attacks: Exploiting Speculative Execution Understanding Contention-Based Channels and Using Them for Defense (HPCA ‘15) Distrustful tenants living within a neutral cloud provider ● Shared hardware can be exploited to leak information ○ e.g. CPU usage vs. operation can expose secret key ● Two bodies of solutions: ○ HW-based: state-of-the-art is either limited in scope or requires impractical architecture changes ○ SW-based: HomeAlone forgoes shared hardware and permits only friendly co-residency, but still vulnerable to an intelligent attacker Threat model of a co-resident attacker ● Distrustful tenants violate confidentiality or compromise availability ● Goal: infer info about victim VM via microarchitectural structures e.g. cache and memory controllers ● Side-channel: victim inadvertently (oops!) leaks data inferred by attacker ● Covert channel: privileged malicious process on victim deliberately leaks data to attacker Known side-channels to transmit a ‘0’ or a ‘1’ (alt. exec.) ● Alternative execution attacks ○ Timing-driven: measure time to access memory portion ○ Access-driven: measure time to access specific cache misses Known side-channels to transmit a ‘0’ or a ‘1’ (parallel exec.) ● Parallel execution attacks ○ No time sharing required ○ E.g. Receiver monitors latency of memory fetch, sender either issues more instructions or idles Formal model of covert channels ● Detection failure (undetectable flow) = same rate of false positives and false negatives for both legitimate and covert traffic ● Network vs. microarchitectural channels: ○ Network receivers read silently ○ Microarch. receivers read destructively (overwrites when reading) ● Main insight: network channels are provably undetectable whereas microarch. -
Full Disclosure
FULL DISCLOSURE David C Frier Atos RSS - 2017 FULL DISCLOSURE: Topics ● About your speaker ● What is -- and is NOT -- a “hacker”? ● Cybercriminals and Researchers ● What is -- and is NOT -- a “zero-day”? ● Disclosure, Responsible and Otherwise ● Bug Bounties About Your Speaker ● David C Frier, CISSP, CISM, CRISC, CCSK ● Client Security Manager for Atos, caring for Xerox’s infrastructure ...but I speak only for myself, not for Atos! ● I’ve been doing Information Security for a dozen years ● I’ve been doing IT of one sort or another for Jack Benny’s age ● Avid player of poker and Ingress, enthusiastic rider of a Trek. ● $FIRST.$LAST@{gmail.com | atos.net} ● Not on LinkedIn ...but feel free to check my profile at Google+ if the Ambien has stopped working. What’s a Hacker? ● Hacker n. (from Wikitionary) 1. (computing) One who is expert at programming and solving problems with a computer. 2. (computing) One who uses a computer to gain unauthorized access to data, or to carry out malicious attacks. 3. (computing) A computer security professional. ● The top discussion item on that wiki entry simply says, Unfortunately, the original sense of this word is no longer primary, and as much as I would like to reclaim the original sense, that battle is long since lost. If you use hacker outside the hacker community, expect to be misunderstood. ● TL;DR - Hacker ≠ Criminal Cybercriminals? ● Cybercriminals may or may not be hackers. ○ They may hire technical capability, and not exercise it themselves ○ They may be only script-kiddies ○ They might not even be criminals: They may be state-sponsored, and thus their actions are legal, under their nation’s laws ● Meanwhile, hacking is: ○ A set of problem-solving approaches ○ A toolbox of techniques ○ Morally neutral ● IFF the goal of the hacking is a crime, then a hacker also happens to be a cybercriminal. -
Paravirtualization (PV)
Full and Para Virtualization Dr. Sanjay P. Ahuja, Ph.D. Fidelity National Financial Distinguished Professor of CIS School of Computing, UNF x86 Hardware Virtualization The x86 architecture offers four levels of privilege known as Ring 0, 1, 2 and 3 to operating systems and applications to manage access to the computer hardware. While user level applications typically run in Ring 3, the operating system needs to have direct access to the memory and hardware and must execute its privileged instructions in Ring 0. x86 privilege level architecture without virtualization Technique 1: Full Virtualization using Binary Translation This approach relies on binary translation to trap (into the VMM) and to virtualize certain sensitive and non-virtualizable instructions with new sequences of instructions that have the intended effect on the virtual hardware. Meanwhile, user level code is directly executed on the processor for high performance virtualization. Binary translation approach to x86 virtualization Full Virtualization using Binary Translation This combination of binary translation and direct execution provides Full Virtualization as the guest OS is completely decoupled from the underlying hardware by the virtualization layer. The guest OS is not aware it is being virtualized and requires no modification. The hypervisor translates all operating system instructions at run-time on the fly and caches the results for future use, while user level instructions run unmodified at native speed. VMware’s virtualization products such as VMWare ESXi and Microsoft Virtual Server are examples of full virtualization. Full Virtualization using Binary Translation The performance of full virtualization may not be ideal because it involves binary translation at run-time which is time consuming and can incur a large performance overhead. -
Vulnerability Assessment
Security Patterns for AMP-based Embedded Systems Doctoral Thesis (Dissertation) to be awarded the degree of Doktor-Ingenieur (Dr. -Ing.) submitted by Pierre Schnarz from Alzenau approved by the Department of Informatics, Clausthal University of Technology 2018 Dissertation Clausthal, SSE-Dissertation 19, 2018 D 104 Chairperson of the Board of Examiners Prof. Dr. Jorg¨ P. Muller¨ Chief Reviewer Prof. Dr. Andreas Rausch 2. Reviewer Prof. Dr. Joachim Wietzke 3. Reviewer Prof. Dr. Jorn¨ Eichler Date of oral examination: December 19, 2018 Für Katrin Declaration I hereby declare that except where specific reference is made to the work of others, the contents of this dissertation are original and have not been submitted in whole or in part for consideration for any other degree or qualification in this, or by any other university. This dissertation is my own work and contains nothing which is the outcome of work done in collaboration with others, except as specified in the text and Acknowledgements. Pierre Schnarz April 2019 Acknowledgements - Danksagung The probability that we may fail in the struggle ought not to deter us from the support of a cause we believe to be just. Abraham Lincoln Viele Menschen haben mich auf dem langen Weg bis zur Fertigstellung dieser Arbeit begleitet. Daher möchte ich mich hier bei all Jenen bedanken, die beigetragen haben mir dies zu ermöglichen. Bei Prof. Dr. Joachim Wietzke bedanke ich mich für die Betreuung meiner Promotion. Gerade die Mitarbeit in seiner Forschungsgruppe und darüber hinaus hat mir die nötige Hartnäckigkeit vermittelt, welche es brauchte um dieses große Projekt zu Ende zu bringen. -
Paravirtualization Poojitha, Umit Full Virtualization
Paravirtualization Poojitha, Umit Full virtualization • Unmodified OS • It doesn’t know about hypervisor • Back and forth between hypervisor and MMU-visible shadow page table: inefficient • Unprivileged instructions which are sensitive: difficult to handle (binary translation VMware ESX) • Cannot access hardware in privileged mode • If guest OS wants real resource information? (Timer, superpages) 2 Paravirtualization • Modify Guest OS • It knows about hypervisor • Applications not modified • Some exposure to hardware and real resources like time • Improved performance (reduce redirections, allowing guest OS to use real hardware resources in a secure manner) • It can allow us to do virtualization without hardware support 3 Discussion – Xen • Memory Management • CPU • Protection • Exception • System call • Interrupt • Time • Device I/O 4 Protection • Privilege of OS must be less than Xen: • In x86, 4 levels of privilege • 3 for applications, Zero for OS - generally • Downgrade guest OS to level 1 or 2 • Xen will be at 0 Wikipedia 5 Exceptions • System calls, Page Faults • Register with Xen: descriptor table for exception handlers • No back and forth between Xen and Guest OS like in full Virtualization • Fast handlers for system call: • When Applications execute system call, it directly goes to Guest OS handler in ring 1 – not to Xen (But not page fault handler it has to go through Xen) • Handlers validated before installing in hardware exception table 6 Time • Guest OS can see: both real and virtual time • Real time • Virtual time • Wall clock time • Why do you want to see time? e.g., need it for TCP: TCP timeouts, RTT estimates 7 Memory Management • TLB flush on context switch (Guest OS – Guest OS) – Undesirable • Software TLB – can virtualize without flushing between switches • Hardware TLB – tag it with address space identifier. -
Software Bug Bounties and Legal Risks to Security Researchers Robin Hamper
Software bug bounties and legal risks to security researchers Robin Hamper (Student #: 3191917) A thesis in fulfilment of the requirements for the degree of Masters of Law by Research Page 2 of 178 Rob Hamper. Faculty of Law. Masters by Research Thesis. COPYRIGHT STATEMENT ‘I hereby grant the University of New South Wales or its agents a non-exclusive licence to archive and to make available (including to members of the public) my thesis or dissertation in whole or part in the University libraries in all forms of media, now or here after known. I acknowledge that I retain all intellectual property rights which subsist in my thesis or dissertation, such as copyright and patent rights, subject to applicable law. I also retain the right to use all or part of my thesis or dissertation in future works (such as articles or books).’ ‘For any substantial portions of copyright material used in this thesis, written permission for use has been obtained, or the copyright material is removed from the final public version of the thesis.’ Signed ……………………………………………........................... Date …………………………………………….............................. AUTHENTICITY STATEMENT ‘I certify that the Library deposit digital copy is a direct equivalent of the final officially approved version of my thesis.’ Signed ……………………………………………........................... Date …………………………………………….............................. Thesis/Dissertation Sheet Surname/Family Name : Hamper Given Name/s : Robin Abbreviation for degree as give in the University calendar : Masters of Laws by Research Faculty : Law School : Thesis Title : Software bug bounties and the legal risks to security researchers Abstract 350 words maximum: (PLEASE TYPE) This thesis examines some of the contractual legal risks to which security researchers are exposed in disclosing software vulnerabilities, under coordinated disclosure programs (“bug bounty programs”), to vendors and other bug bounty program operators. -
KVM: Linux-Based Virtualization
KVM: Linux-based Virtualization Avi Kivity [email protected] Columbia University Advanced OS/Virtualization course Agenda Quick view Power management Features Non-x86 KVM Execution loop Real time Memory management Xenner Linux Integration Community Paravirtualization Conclusions I/O Copyright © 2007 Qumranet, Inc. All rights reserved. At a glance KVM – the Kernel-based Virtual Machine – is a Linux kernel module that turns Linux into a hypervisor Requires hardware virtualization extensions Supports multiple architectures: x86 (32- and 64- bit) s390 (mainframes), PowerPC, ia64 (Itanium) Competitive performance and feature set Advanced memory management Tightly integrated into Linux 3 Copyright © 2007 Qumranet, Inc. All rights reserved. The KVM approach Reuse Linux code as much as possible Focus on virtualization, leave other things to respective developers Integrate well into existing infrastructure, codebase, and mindset Benefit from semi-related advances in Linux Copyright © 2007 Qumranet, Inc. All rights reserved. VMware Console User User User VM VM VM VM Hypervisor Driver Driver Driver Hardware Copyright © 2007 Qumranet, Inc. All rights reserved. Xen User User User Domain 0 VM VM VM Driver Driver Hypervisor Driver Hardware Copyright © 2007 Qumranet, Inc. All rights reserved. KVM Ordinary LinuxOrdinary User User User Ordinary ProcessLinux VM VM VM ProcessLinux Process KVM Modules Linux Driver Driver Driver Hardware Copyright © 2007 Qumranet, Inc. All rights reserved. KVM model enefits Reuse scheduler, memory management, bringup Reuse Linux driver portfolio Reuse I/O stack Reuse management stack Copyright © 2007 Qumranet, Inc. All rights reserved. KVM Process Model task task guest task task guest kernel 9 Copyright © 2007 Qumranet, Inc. All rights reserved. KVM Execution Model Three modes for thread execution instead of the traditional two: User mode Kernel mode Guest mode A virtual CPU is implemented using a Linux thread The Linux scheduler is responsible for scheduling a virtual cpu, as it is a normal thread 10 Copyright © 2007 Qumranet, Inc. -
Vmware Security Best Practices
VMware Security Best Practices Jeff Turley Lewis University April 25, 2010 Abstract Virtualization of x86 server infrastructure is one of the hottest trends in information technology. With many organizations relying on virtualization technologies from VMware and other vendors to run their mission critical systems, security has become a concern. In this paper, I will discuss the different types of virtualization technologies in use today. I will also discuss the architecture of VMware vSphere and security best practices for a VMware vSphere environment. 2 Table of Contents Introduction Page 5 Business Case For Virtualization Page 5 Understanding Virtualization Page 6 CPU Virtualization Page 6 The Hypervisor Page 11 Understanding VMware vSphere Page 12 VMware vSphere Architecture Page 12 VMware vSphere Components Page 13 The VMware vSphere Virtual Data Center Page 14 VMware vSphere Distributed Services Page 18 VMware Virtual Networking Page 25 VMware Virtual Storage Architecture Page 28 VMware vCenter Server Page 29 Securing a VMware Virtual Environment Page 30 VMware vSphere Network Security Page 32 VMware vSphere Virtual Machine Security Page 35 VMware vSphere ESX/ESXi Host Security Page 37 VMware vSphere vCenter Server Security Page 37 VMware vSphere Console Operating System (COS) Security Page 38 Conclusion Page 39 References Page 40 3 Table of Figures Figure 1: Operating system and applications running directly on physical hardware………………………………………………………..….....……………..…..Page 7 Figure 2: Operating system and applications running with -
Open Enterprise Server 2015 SP1 OES Cluster Services Implementation Guide for Vmware
Open Enterprise Server 2015 SP1 OES Cluster Services Implementation Guide for VMware July 2020 Legal Notices For information about legal notices, trademarks, disclaimers, warranties, export and other use restrictions, U.S. Government rights, patent policy, and FIPS compliance, see https://www.microfocus.com/about/legal/. Copyright © 2020 Micro Focus Software, Inc. All Rights Reserved. Contents About This Guide 5 1 Getting Started with OES Cluster Services in an ESXi Virtualized Environment 7 1.1 Configuration Overview . 8 1.2 Understanding Virtualization . 8 1.2.1 Where Is Virtualization Today? . 9 1.2.2 Why Use Virtualization?. 9 1.2.3 Why Use Novell Cluster Services? . 9 1.2.4 Server versus Service Virtualization . .9 1.3 Architectural Scenarios . 11 1.3.1 Only Service Virtualization. 11 1.3.2 Only Server Virtualization . 12 1.3.3 NCS on Host Machines Managing Xen or KVM Guest Machines . 12 1.3.4 NCS Managing Services on Guest Machines . 13 1.3.5 NCS Managing Services on a Cluster of Physical and Guest Machines. 13 1.4 Design and Architecture Considerations . 14 1.4.1 Challenges of Server Virtualization . 14 1.4.2 Cost of Server Virtualization . 14 1.4.3 Challenges of Service Virtualization . 15 1.4.4 Cost of Service Virtualization. 15 1.4.5 Fault Tolerance and Scalability . 15 1.4.6 Planning Considerations . 15 1.4.7 Full Virtualization versus Paravirtualization . 15 1.4.8 Comparing Architectures . 16 2 Planning for the Virtualized Environment 17 2.1 Things to Explore . 17 2.2 Infrastructure Dependencies . 17 2.3 LAN and SAN Connectivity . -
Operating System Virtualization
Introduction to virtualisation technology Predrag Buncic CERN CERN School of Computing 2009 Introduction to Virtualisation Technology History . Credit for bringing virtualization into computing goes to IBM . IBM VM/370 was a reimplementation of CP/CMS, and was made available in 1972 . added virtual memory hardware and operating systems to the System/370 series. Even in the 1970s anyone with any sense could see the advantages virtualization offered . It separates applications and operating systems from the hardware . With VM/370 you could even run MVS on top - along with other operating systems such as Unix. In spite of that, VM/370 was not a great commercial success . The idea of abstracting computer resources continued to develop 2 Predrag Buncic – CERN Introduction to Virtualisation Technology Resource virtualization . Virtualization of specific system computer resources such as . Memory virtualization . Aggregates RAM resources from networked systems into Memory virtualized memory pool . Network virtualization . Creation of a virtualized network addressing space within or across network subnets . Using multiple links combined to work as though they Networking offered a single, higher-bandwidth link . Virtual memory . Allows uniform, contiguous addressing of physically separate and non-contiguous memory and disk areas . Storage virtualization Storage . Abstracting logical storage from physical storage . RAID, disk partitioning, logical volume management 3 Predrag Buncic – CERN Introduction to Virtualisation Technology Metacomputing . A computer cluster is a group of linked computers, working together closely so that in many respects they form a single computer. The components of a cluster are commonly connected to each other through fast local area networks. Grids are usually computer clusters, but more focused on throughput like a computing utility rather than running fewer, tightly-coupled jobs .