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.
During an investigation of a malware campaign, I discovered that multiple emails were bypassing a specific email security system. Interestingly, there were no bypass techniques used. Instead, the flood of spear-phishing emails made the email security system allow some of the emails, at which point I began my research on Microsoft Outlook. The issue in this case was that the specially crafted malicious link parsing on the security system was weak.
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.
