A new advisory from Qualys discloses a local privilege escalation bug in SUID-set program ‘pkexec’. The flaw has been designated the CVE ID of CVE-2021-4034 and nicknamed “pwnkit” by the vulnerability finders. The CVSSv3 base score is calculated to be a high 7.8 out of 10.0. The vulnerable program is a part of Polkit, which manages process privileges.

Threat actors go to great lengths to hide the intentions of the malware they produce. For instance, binaries are often encrypted or packed. Typically, encrypting binaries is enough to thwart automated analysis platforms such as Cuckoo or other automated malware sandboxes. The implication is that automated detection of malicious programs might not be successful.

Since 2009, more than 12 years ago, all major Linux distributions have been incorporating a high severity security hole that remained unnoticed until just recently. The vulnerability and exploit, dubbed “PwnKit” (CVE-2021-4034), uses the vulnerable “pkexec” tool, and allows a local user to gain root system privileges on the affected host. Polkit (formerly PolicyKit) is a component for controlling system-wide privileges in Unix-like operating systems.

This week, Linux maintainers and vendors disclosed a heap overflow vulnerability in the Linux Kernel. The vulnerability has been issued a Common Vulnerability and Exposures ID of CVE-2022-0185 and is rated as a High (7.8) severity. The flaw occurs in the Filesystem Context system when handling legacy parameters. An attacker can leverage this flaw to cause a DDoS, escape container environments, and elevate privileges.

We are excited to welcome Windows hosts to the Teleport Access Plane. For the past 5 years we’ve helped refine our Access Plane for Linux hosts, providing short-lived certificate-based access, RBAC and developer-friendly access to resources. As we’ve rolled Teleport to larger organizations, we found that people wanted the same convenience and security of Teleport but for Windows hosts.

A world without Linux is hard to imagine. Every Google search we run is accomplished on Linux-based servers. Behind the Kindle we enjoy reading, to the social media sites we spend scrolling away every day sits the Linux kernel. Would you believe your ears if I tell you the world’s top 500 supercomputers run on Linux? No wonder Linux has permeated into every aspect of the digital age, not to mention its steadily growing enterprise user base.

Almost all tasks within a Linux system, whether it’s an application, system daemon, or certain types of user activity, are executed by one or more processes . This means that monitoring processes is key to detecting potentially malicious activity in your systems, such as the creation of unexpected web shells or other utilities.

The CVE-2021-33909, named Sequoia, is a new privilege escalation vulnerability that affects Linux’s file system. It was disclosed in July, 2021, and it was introduced in 2014 on many Linux distros; among which we have Ubuntu (20.04, 20.10 and 21.04), Debian 11, Fedora 34 Workstation and some Red Hat products, too. This vulnerability is caused by an out-of-bounds write found in the Linux kernel’s seq_file in the Filesystem layer.