Microsoft Patch Tuesday updates for March 2019 address 64 vulnerabilities, including two Windows zero-day flaws that have been exploited in targeted attacks.
Four of the vulnerabilities addressed by Microsoft were publicly disclosed before fixes were released, they have been classified by Microsoft as “important.” 17 vulnerabilities impacting Windows and Microsoft’s Edge and Internet Explorer web browsers were rated as “critical”.
The first zero-day addressed by Microsoft is tracked as CVE-2019-0808. This flaw was recently disclosed by Google’s Threat Analysis Group after it has observed targeted attacks exploiting the issue alongside a recently addressed flaw in Chrome flaw (CVE-2019-5786).
The CVE-2019-0808 resides in the Win32k component, it could be exploited by an authenticated attacker to elevate privileges and execute arbitrary code in kernel mode.
Experts argue the Windows zero-day could be exploited only on Windows 7 due to recent exploit mitigations added in newer versions of Microsoft OS. To date, experts only observed active exploitation against Windows 7 32-bit systems.
Microsoft did not reveal technical details about the attacks that involved the Windows zero-day.
No information has been provided about the attacks involving this vulnerability.
The second zero-day addressed by Microsoft Patch Tuesday updates for March 2019 is a privilege escalation vulnerability tracked as CVE-2019-0797 that affects the Win32k component.
The issue could be exploited by an authenticated attacker to run a specially crafted application that could exploit the vulnerability and take control of an affected system.
“An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory.” reads the security advisory.
“An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.”
The CVE-2019-0797 affects Windows 10, Windows 8.1, Windows Server 2012, Windows Server 2016, and Windows Server 2019. According to Microsoft, the vulnerability is hard to exploit against the latest versions of Windows.