Two Linux vulnerabilities give exploiters root privileges

Linux administrators are urged to watch for and install patches to fix two major vulnerabilities in the operating system.

Both discovered by researchers at Qualys, one is a stack exhaustion denial-of-service vulnerability in systemd, described as a near-ubiquitous utility available on major Linux operating systems and the second is a flaw in the Linux kernel filesystem layer that could allow an unprivileged user to gain root privileges.

Systemd vulnerability

“Any unprivileged user can exploit this vulnerability to crash systemd and hence the entire operating system (a kernel panic),” the company said in a blog. Systemd is a software suite that’s included in most Linux-based OSes which provides an array of system components for Linux operating systems, including a system and service manager that runs as PID 1 and starts the rest of the system.

The vulnerability dates back to April, 2015, when it was introduced to a version added to the operating system.

Red Hat and Ubuntu have issued patches for their Linux distributions.

Filesystem flaw

Separately, Linux administrators have been warned to watch for patches to fix a vulnerability in the Linux kernel’s filesystem layer that could allow any unprivileged user to gain root privileges on a vulnerable host. It is said to affect most Linux operating systems.

Under certain circumstances if an unprivileged local attacker creates, mounts, and deletes a deep directory structure whose total path length exceeds 1GB, they can obtain full root privileges. Qualys has shown that this works on default installations of Ubuntu 20.04, Ubuntu 20.10, Ubuntu 21.04, Debian 11, and Fedora 34 Workstation.

Red Hat released a patch on July 13th.

Given the breadth of the attack surfaces for both of these vulnerabilities, Qualys recommends users apply patches for them immediately.

Would you recommend this article?


Thanks for taking the time to let us know what you think of this article!
We'd love to hear your opinion about this or any other story you read in our publication.

Jim Love, Chief Content Officer, IT World Canada

Featured Download

Howard Solomon
Howard Solomon
Currently a freelance writer, I'm the former editor of and Computing Canada. An IT journalist since 1997, I've written for several of ITWC's sister publications including and Computer Dealer News. Before that I was a staff reporter at the Calgary Herald and the Brampton (Ont.) Daily Times. I can be reached at hsolomon [@]

Related Tech News

Tech Jobs

Our experienced team of journalists and bloggers bring you engaging in-depth interviews, videos and content targeted to IT professionals and line-of-business executives.

Tech Companies Hiring Right Now