How to Simplify Working With Kernels

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What Is A Kernel?

The kernel is a piece of software that is at the core of an operating system. It usually has complete control over all of the server systems. It is normally the first program loaded after the bootloader has completed its tasks. The kernel then handles the rest of the start-up tasks as well as i/o requests from the system’s software. It then translates those requests into hardware instructions for the CPU (central processing unit).

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PHP-FPM/Nginx Vulnerability – CVE-2019-11043

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A new vulnerability in PHP-FPM has been noted which could lead to remote code execution on nginx. An earlier message on Twitter exposed the CVE-2019-11043 bug:

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How to Upgrade and Patch cPanel / WHM

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Pre-Flight Check

  • These instructions are intended specifically for checking your version of cPanel or WHM via the command line or the WHM dashboard.
  • I’ll be working from a Liquid Web Managed CentOS 7 server, and I’ll be logged in as root.

Step #1: Log In to WHM

First, log in to WHM. You’ll arrive at your WHM dashboard:

How to Upgrade and Patch cPanel WHM

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Information on CVE-2015-3456 QEMU Vulnerability (VENOM)

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Overview

VENOM, or Virtualized Environment Neglected Operations Manipulation, was made public on May 13, 2015. The vulnerability is in QEMU, a generic and open source machine emulator and virtualizer that is utilized by Xen, KVM, and other modern hypervisors / virtualization platforms.

Impact

Specifically a flaw with how QEMU handles out-of-bounds memory access, exploitation can cause the entire hypervisor to crash and may allow an attacker to access other virtual machines outside of their own.

Summary
  • Made public on May 13, 2015
  • This flaw exploits QEMU, a generic and open source machine emulator.
  • Allows for an attacker to access other virtual machines outside of their own.
Resolution

A patch is available, and Liquid Web’s Heroic Support has proactively scheduled a reboot to patch all affected servers.

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CVE-2015-0235 Vulnerability Info for Red Hat and CentOS

Reading Time: < 1 minuteA vulnerability found in the glibc library, specifically a flaw affecting the gethostbyname() and gethostbyname2() function calls, that allows a remote attacker to potentially execute arbitrary code. CentOS 5, CentOS 6, and CentOS 7 are potentially affected, thus we want to highlight the following information.

Liquid Web package repositories have been updated. Many servers (barring those with updates disabled) have received an update that patches this vulnerability, however, a reboot will still be required in those cases.

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CVE-2014-9322 Vulnerability Info for Red Hat and CentOS

Reading Time: < 1 minuteA vulnerability found in the Linux kernel, specifically a flaw in fault handling associated with the Stack Segment (SS), allows an unprivileged user to potentially gain privileges. CentOS 4, CentOS 5, CentOS 6, and CentOS 7 are potentially affected, thus we want to highlight the following information.
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Patch OpenSSL Against CCS Injections on Ubuntu

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What is OpenSSL?

OpenSSL is a common cryptographic library which provides encryption, specifically SSL/TLS, for popular applications such as Apache (web), MySQL (database), e-mail, virtual private networks (VPNs), and more.

What is “the CCS Injection Vulnerability”?

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Patch OpenSSL on CentOS Againt CCS Injection

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What is OpenSSL?

OpenSSL is a common cryptographic library which provides encryption, specifically SSL/TLS, for popular applications such as Apache (web), MySQL (database), e-mail, virtual private networks (VPNs), and more.

What is “the CCS Injection Vulnerability”?

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CVE-2014-0196 Vulnerability Info for CentOS and Ubuntu

Reading Time: < 1 minuteA vulnerability found in the Linux kernel, specifically a flaw with the pseudo tty (pty) device, allows an unprivileged user to cause a denial of service (system crash) or potentially gain administrator privileges. A small number of CentOS and Ubuntu versions are vulnerable, thus we want to highlight the following information:

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Update and Patch OpenSSL for Heartbleed Vulnerability

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What is OpenSSL?

OpenSSL is a common cryptographic library which provides encryption, specifically SSL/TLS, for popular applications such as Apache (web), MySQL (database), e-mail, virtual private networks (VPNs), and more.

What is “the Heartbleed Bug”?

The Heartbleed Bug is a severe vulnerability in OpenSSL, known formally as “TLS heartbeat read overrun (CVE-2014-0160)“. As of April 07, 2014, a security advisory was released by OpenSSL.org, along with versions of OpenSSL that fix this vulnerability.

What are the risks?

In short, the risks are many. In most circumstances, this flaw allows an attacker to read the memory of servers running vulnerable versions of OpenSSL. This would allow attackers to impersonate users and services, and provide a means for data theft. For example, the exposed memory could include sensitive information such as private keys. If private keys are leaked, then it is possible that SSL certificates are compromised, and in that case should definitely be reissued.

What do I do?
  • Update and reboot your server immediately.
  • After the server has been rebooted, change all passwords associated with the server.
  • Consider getting your SSL certificates reissued.
Pre-Flight Check
  • These instructions are intended for patching OpenSSL on CentOS 6 against the “TLS heartbeat read overrun (CVE-2014-0160)” vulnerability.
  • I’ll be working from a Liquid Web Core Managed CentOS 6.5 server, and I’ll be logged in as root.

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