?Serious Linux kernel security bug fixed

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Sometimes old fixed bugs come back to bite us. That’s the case with CVE-2017-1000253, a Local Privilege Escalation Linux kernel bug.

This is a problem with how the Linux kernel loaded Executable and Linkable Format (ELF) executables. If an ELF application was built as Position Independent Executable (PIE), the loader could allow part of that application’s data segment to map over the memory area reserved for its stack. This could cause memory corruption. Then, an otherwise unprivileged local user with access to a Set owner User ID (SUID) or otherwise privileged flawed PIE binary, could gain higher-level user privileges.

Linux processes

Qualys, a security company, worked out a way to exploit this hole. By smashing the PIE’s .dynamic section with a stack-based string operation, they found they could force the ld.so dynamic linker to load and execute their own shared library.

This security hole may sound complicated, but it’s relatively easy to exploit. Since it could give an ordinary user super-user privileges it’s potentially very dangerous.

This bug, and its fix, are actually old. It was first uncovered in 2015 by Michael Davidson, a Google software engineer. It was fixed in the 4.0 Linux kernel. To be exact, Davidson repaired the kernel bug with a patch committed on April 14, 2015.

What neither Davidson, nor anyone, realized at the time was that what appeared to be a minor bug could be exploited.

Since the bug was patched over two years ago, you might be wondering, “Why does this matter?”

The problem is that the bug lived on in long-term support (LTS) versions of Linux, which are often used in server Linux distributions. In particular, Qualys found that “All versions of CentOS 7 before 1708 (released on September 13, 2017), all versions of Red Hat Enterprise Linux 7 before 7.4 (released on August 1, 2017), and all versions of CentOS 6 and Red Hat Enterprise Linux 6 are exploitable.” The bug is also present in Debian-based Linux distributions.

If you’re running an up-to-date Linux desktop, you have nothing to worry about. These use modern kernels rather than LTS kernels.

With a Common Vulnerability Scoring System, version 3 (CVSSv3) severity score of 7.8, system admins should patch the bug as soon as possible. Since the major Linux distributors were aware of the security hole before it was announced, all a system administrator needs to do is their usual package management program to patch the kernel or install a patched kernel, and reboot.

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Red Hat Launches Cloud Computing Management Certification for Enterprise Linux OpenStack Platform

The cloud computing management certification would offer a recognized career track to the technical professionals, and confidence in OpenStack ecosystem to the customers.

redhatGREATRESPONDER.COM – This was announced by the open source software giant Red Hat on Monday, August 11, 2014 that it is going to start a new career track for the professionals to become certified professionals in the domain of cloud computing management based on the Red Had Enterprise Linux OpenStack Platform. This was announced through an official press release statement of the company. According to the official statement, this new technical career path would be stated as the part of the largest commercial ecosystem based on OpenStack cloud computing platform called as Red Hat OpenStack Cloud Infrastructure Partner Network.

While explaining the purpose of the new career path, it was further elaborated that this program would enable the technical professionals to acquire the structured knowledge and expertise in the domain of cloud computing management based on the fast growing OpenStack based cloud platform. It was further informed that the organized track to acquire the knowledge to manage the cloud ecosystem based on Red Hat supported platform would develop the confidence in the customers and partners across the globe. The professionals certified under this certification would be able to get the priority while seeking the technical jobs in the field of cloud computing.

Meanwhile, it was informed that Red Had is closely working with numerous providers of cloud computing management solutions such as, HP, BMC and many others, which are the partners of Red Hat’s OpenStack Cloud Infrastructure Partner Network. They have already contributed a lot in developing the certification course to make sure that the certificate serves the desired purposes.

The General Manager at Red Hat’s Visualization and OpenStack division, Mr. Radhesh Balakrishnan, in his statement said, “As OpenStack is becoming a core element of the enterprise cloud strategy for many customers, Red Hat Enterprise Linux OpenStack Platform is architected and backed by the broadest partner ecosystem to be the preferred platform. The growth and maturity of the ecosystem reflects the evolution of the product moving from addressing infrastructure-centric alignment to help with early deployments to now be well-managed, to be part of enterprise hybrid cloud implementations.”

The corporate representatives of both HP and BMC were of the view that this certification would be very beneficial for the entire Red Hat’s cloud ecosystem.

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