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.
“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.
The Trustwave Threat Hunting team has authored a practical guide to help the cybersecurity community address the Linux “polkit” Local Privilege Escalation vulnerability (CVE-2021-4034) by identifying common behavior in exploitation.
Trustwave security and engineering teams became aware of the vulnerability in Polkit's pkexec component identified as CVE-2021-4034 (PwnKit) on January 25. We immediately investigated the vulnerability and potential exploits and continue to actively monitor the situation for our clients. Check your distribution for specific patches. As part of a strong patch management program, ensuring your infrastructure and applications are up to date is critical for mitigating cyber risk..
In January 2022, Microsoft disclosed a remote code execution vulnerability for Internet Information Server (IIS) identified as CVE-2022-21907, which they have subsequently reported as wormable. Through Microsoft, Corelight Labs was able to review a proof of concept for an attack against the vulnerability. This blog presents an open source detection method that Corelight Labs is releasing to detect exploit attempts of CVE-2022-21907.
The Log4Shell vulnerability took the Java community by surprise at the end of 2021, and many organizations are still mitigating its impact. To help development teams stay informed as the situation unfolds, Snyk has created and continues to update its Log4j vulnerability resource center.