NMAP Network Mapper

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Managine Hadoop Cluster

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VENOM Vulnerability

How to Patch and Protect Linux Server against the VENOM Vulnerability # CVE-2015-3456 A very serious security problem has been found in the virtual floppy drive QEMU's code used by many computer virtualization platforms including Xen, KVM, VirtualBox, and the native QEMU client. It is called VENOM vulnerability. How can I fix VENOM vulnerability and protect my Linux server against the attack? How do I verify that my server has been fixed against the VENOM vulnerability? This is tagged as high severity security bug and it was announced on 13th May 2015. The VENOM vulnerability has existed since 2004, when the virtual Floppy Disk Controller was first added to the QEMU codebase. Since the VENOM vulnerability exists in the hypervisor’s codebase, the vulnerability is agnostic of the host operating system (Linux, Windows, Mac OS, etc.). What is the VENOM security bug (CVE-2015-3456)? An out-of-bounds memory access flaw was found in the way QEMU's virtual Floppy Disk Controller (F...
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6 Stages of Linux Boot Process

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Press the power button on your system, and after few moments you see the Linux login prompt. Have you ever wondered what happens behind the scenes from the time you press the power button until the Linux login prompt appears? The following are the 6 high level stages of a typical Linux boot process. 1. BIOS BIOS stands for Basic Input/Output System Performs some system integrity checks Searches, loads, and executes the boot loader program. It looks for boot loader in floppy, cd-rom, or hard drive. You can press a key (typically F2 of ESC, but it depends on your system) during the BIOS startup to change the boot sequence. Once the boot loader program is detected and loaded into the memory, BIOS gives the control to it. So, in simple terms BIOS loads and executes the MBR boot loader. 2. MBR MBR stands for Master Boot Record. It is located in the 1st sector of the bootable disk. Typically /dev/hda, or /dev/sda MBR is less than 512 bytes in size. This h...
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