In November 2021, a vulnerability was discovered in a ubiquitous Linux module named Polkit. Developed by Red Hat, Polkit facilitates the communication between privileged and unprivileged processes on Linux endpoints. Due to a flaw in a component of Polkit — pkexec — a local privilege escalation vulnerability exists that, when exploited, will allow a standard user to elevate to root.
A number of security vulnerabilities have been identified on the popular freeware, Samba, which implements the Server Message Block (SMB) protocol that allows users to access files, printers, and other commonly shared resources over a network. These flaws enable remote attackers the ability to execute arbitrary code with the highest privileges on affected installations. The most prominent is CVE-2021-44142, which affects all versions of Samba before 4.13.17.
Last week, a critical vulnerability identified as CVE-2022-0185 was disclosed, affecting Linux kernel versions 5.1 to 5.16.1. The security vulnerability is an integer underflow in the Filesystem Context module that allows a local attacker to run arbitrary code in the context of the kernel, thus leading to privilege escalation, container environment escape, or denial of service.
Since organizations around the globe began investing more aggressively in their digital transformation by migrating and modernizing applications within the cloud, the value of audit logging has shifted. It has expanded from industries like finance and healthcare to nearly any company with a digital strategy.
On Jan. 18, 2022, researchers found a heap base buffer overflow flaw (CVE-2022-0185) in the Linux kernel (5.1-rc1+) function “legacy_parse_param” of filesystem context functionality, which allows an out-of-bounds write in kernel memory. Using this primitive, an unprivileged attacker can escalate its privilege to root, bypassing any Linux namespace restrictions.
What do Linux vulnerabilities and natural disasters have in common? Something seemingly dormant can suddenly spring to life, exposing activity beneath the surface. Several days ago, a security researcher published a high-severity vulnerability named PwnKit that impacts most major Linux distributions. The scary part? It’s existed since May of 2009. Polkit is a component for controlling privileges in Unix-like operating systems and is included by default on most major Linux distributions.
On January 25, 2022, Qualys announced the discovery of a local privilege escalation vulnerability that it identified as PwnKit. The PwnKit vulnerability affects PolicyKit’s pkexec, a SUID-root program installed by default on many Linux distributions. The same day of the announcement, a proof of concept (PoC) exploit was built and published by the security research community.
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.
“Crowdsourced security provides a way for security teams to expand their efficiency, especially when it comes to managing their external attack surface,” said Rickard Carlsson, Co-founder and CEO of Detectify. “Hackers have eyes and ears all over the web, and they’re constantly monitoring attack surfaces for exploitable entry points.
