Security Vulnerability Puts Linux Kernel at Risk

A security vulnerability that could allow an external attacker to escalate privileges and execute malicious code puts the Linux kernel at risk.

The security vulnerability impacts the Advanced Linux Sound Architecture (ALSA), which is a software framework that establishes an application programming interface (API) for sound card drivers in the Linux kernel. While the potential damage from escalated privileges is high, IT decision-makers should note that a patch has already been made available.

An active development community helps keep security concerns associated with Linux at bay. However, IT managers and users must stay alert to potential concerns and work to apply recommended fixes at the earliest opportunity.

Exploiting the Security Vulnerability

The bug has been tracked as a security vulnerability and assigned the identifier CVE-2017-15265. Its existence has been confirmed by Kernel.org, SecurityWeek reported.

Cisco issued an advisory note that provides additional information on the bug. The networking firm reported that an errant outsider could exploit the flaw by running a crafted application on a targeted system.

The ALSA code in the kernel enables attackers to call a function, erase its output and still use the output in a subsequent function, according to Bleeping Computer. This flaw is a well-known attack vector and a memory management concern. It is commonly referred to as a use-after-free vulnerability.

The Risk to Critical Business Information

A knowledgeable attacker could use the ALSA vulnerability to extend his or her limited account privileges to root, potentially placing sensitive information at risk of exposure.

Cisco suggested that attackers looking to make the most of this security vulnerability would need to hold local access to the system they are targeting. The good news for IT managers is that the high level of access necessary is likely to reduce the chances of a successful attack.

Most crucially of all, the Linux kernel team fixed the security vulnerability in v4.13.4-2, according to Bleeping Computer. The patch is now being pushed to the community from an array of Linux distributors.

Keeping Linux Secure

Even though Linux tends to suffer fewer attacks than other systems, potential dangers are not unheard of. Experts warned in the summer that a vulnerability known as the Stack Clash bug could enable attackers to gain full root privileges. Around the same time, Russian security firm Dr. Web discovered two new forms of a Linux Trojan.

Fortunately, an active community around Linux helps keep errant activities at bay. Linux kernel creator Linus Torvalds recently praised the community for its continued efforts to find and eradicate bugs, particularly via fuzzing, an automated quality assurance technique used to uncover coding errors and security loopholes.

As always, users and IT managers should take note of these developments and run patches as known concerns emerge. In its note, Cisco advised administrators to apply appropriate updates, to only allow trusted entities to access local systems and to monitor affected systems.

Mark Samuels

Tech Journalist

Mark Samuels is an experienced business technology journalist with an outstanding track record in research. He...