Call us today on: +44 (0)203 88 020 88
SecureTeamSecureTeamSecureTeamSecureTeam
  • Home
  • Our Services
    • Infrastructure Testing
      • Internal Network Penetration Test
      • External Network Penetration Test
      • Wireless Network Penetration Test
      • Vulnerability Assessment
      • Network Segregation Test
      • Voice over IP (VoIP) Penetration Test
    • Application Testing
      • Web Application Penetration Test
      • Mobile Application Penetration Test
      • Desktop Application Security Assessment
      • Citrix Breakout Test
    • Configuration Review
      • Windows Server Build Review
      • Linux Server Build Review
      • Citrix Configuration Review
    • Information Assurance
      • ISO 27001 Gap Analysis
    • Cyber Essentials
  • News
  • Articles
  • About
    • About SecureTeam
    • STORM Appliances
      • Installing a STORM Device
      • Returning a STORM Device
    • White-Label Consultancy
    • Jobs
    • Cookie Policy
    • Quality Policy
    • Security Policy
    • Privacy Notice
    • Website Terms & Conditions
  • Contact Us

News

Home  >  News  >  Vulnerabilities  >  Zombieload – a new class of Intel CPU vulnerability
NextPrevious

Zombieload – a new class of Intel CPU vulnerability

News, Vulnerabilities | 22 May, 2019 | 0

A team including some of the researchers who discovered the Spectre and Meltdown vulnerabilities in AMD and Intel CPU announced a new class of vulnerability affecting Intel CPU which they called Zombieload.

Like Spectre and Meltdown, the Zombieload vulnerability exploits weaknesses in the implementation of speculative execution in Intel CPUs.  The different attack names reflect the different parts of the CPU architecture that are being abused in the attack.

For Meltdown and Spectre, the attacker is able to gain access to application and kernel data stored in memory.

For Zombieload, the attacker is able to gain access to data stored in micro-architectural buffers within the CPU itself.  This means a process in one hyperthread on a CPU core can get access to data loaded by a another hyperthread running in the same CPU.  Since the placement of processes within threads across CPU cores is usually arbitrary (controlled by the operating system), the two threads on the same CPU core could come from different application or even a different virtual machines for example.

The researchers say in their paper:

ZombieLoad is a transient-execution attack which observes the values of memory loads on the current physical CPU. ZombieLoad exploits that the fill buffer is accessible by all logical CPUs of a physical CPU core and that it does not distinguish between processes or privilege levels.

How to mitigate against Zombieload

Systems Administrators responsible for servers running multiple Virtual Machines should consider adjusting the mapping of VMs against available physical CPUs to avoid Virtual Machines of different security value running on the same physical CPU.  It would be even better to avoid running Virtual Machines of different security value (such as one VM used for testing and another VM which is a live Web server) on the same physical server.

While the main hosting providers and operating system vendors are issuing patches which mitigate the recently published flaws (both in their own software and rolling out CPU microcode updates from Intel), it would appear that the only real defence against this new class of attacks is to disable hyperthreading. The loss of hyperthreading could impact system performance by up to 40% according to a security advisory for their laptops from Apple.

Intel has published their own detailed advisory which has more optimistic predictions for the performance impact of the fixes

 

Subscribe to our monthly cybersecurity newsletter
Stay up-to-date with the very latest cybersecurity news & technical articles delivered straight to your inbox
We hate spam as much as you do. We will never give your email address out to any third-party.
Meltdown, patching, Spectre, vulnerability management, Zombieload

Related Post

  • Amex and Snapchat used in Open Redirect Attacks

    By Mark Faithfull

    Google Workspace and Microsoft 365 users have been targeted in phishing attacks that have resulted in the attackers stealing credentials. The attackers exploited known flaws in Snapchat and American Express websites to trigger open redirectsRead more

  • VMware Patch Critical Authentication Bypass Flaw

    By Mark Faithfull

    VMware released a critical security advisory this week to warn users of security vulnerabilities that have been found in a variety of their systems. VMware Workspace ONE Access, Access Connector, Identity Manager, Identity Manager Connector,Read more

  • Critical Confluence Vulnerability Exploited in the Wild

    By Mark Faithfull

    A vulnerability in Atlassian’s Questions for Confluence app has been found that includes hardcoded credentials that remote attackers can exploit to access the Confluence Server or Confluence Data Center it is hosted on. The versionsRead more

  • Microsoft Exchange Servers Open to Backdoor Hack

    By Mark Faithfull

    Microsoft have warned customers of a form of attack capable of targeting unpatched Microsoft Exchange servers. The attacks taking place in the first 5 months of this year saw threat actors using Internet Information ServicesRead more

  • Source Code for Stealer Malware Released Online

    By Mark Faithfull

    An information stealing malware has had its source code released by the developer on a popular hacking forum. Cyber criminals have had free access to this malware since the start of this month, and itRead more

NextPrevious

Recent Posts

  • Amex and Snapchat used in Open Redirect Attacks
  • VMware Patch Critical Authentication Bypass Flaw
  • Critical Confluence Vulnerability Exploited in the Wild
  • LinkedIn the Top Phishing Brand in Q2 2022
  • Microsoft Exchange Servers Open to Backdoor Hack

Recent Comments

    Archives

    • August 2022
    • July 2022
    • June 2022
    • May 2022
    • April 2022
    • March 2022
    • February 2022
    • January 2022
    • December 2021
    • November 2021
    • October 2021
    • September 2021
    • August 2021
    • July 2021
    • June 2021
    • May 2021
    • April 2021
    • March 2021
    • February 2021
    • January 2021
    • December 2020
    • November 2020
    • October 2020
    • September 2020
    • August 2020
    • July 2020
    • June 2020
    • April 2020
    • March 2020
    • February 2020
    • January 2020
    • December 2019
    • November 2019
    • October 2019
    • September 2019
    • August 2019
    • July 2019
    • June 2019
    • May 2019
    • April 2019
    • March 2019
    • February 2019
    • January 2019
    • December 2018
    • November 2018
    • July 2018
    • June 2018
    • April 2018
    • January 2018
    • October 2017
    BCS Cyber Essentials Cyber Essentials Cyber Essentials PLUS ISO 9001 ISO 27001
    information. secured.
    • Home
    • Our Services
      • Infrastructure Testing
        • Internal Network Penetration Test
        • External Network Penetration Test
        • Wireless Network Penetration Test
        • Vulnerability Assessment
        • Network Segregation Test
        • Voice over IP (VoIP) Penetration Test
      • Application Testing
        • Web Application Penetration Test
        • Mobile Application Penetration Test
        • Desktop Application Security Assessment
        • Citrix Breakout Test
      • Configuration Review
        • Windows Server Build Review
        • Linux Server Build Review
        • Citrix Configuration Review
      • Information Assurance
        • ISO 27001 Gap Analysis
      • Cyber Essentials
    • News
    • Articles
    • About
      • About SecureTeam
      • STORM Appliances
        • Installing a STORM Device
        • Returning a STORM Device
      • White-Label Consultancy
      • Jobs
      • Cookie Policy
      • Quality Policy
      • Security Policy
      • Privacy Notice
      • Website Terms & Conditions
    • Contact Us
    SecureTeam