Zero-day vulnerability in Windows

Privilege escalation
CVE-2017-0005

The vulnerability was used by Zirconium cyber-espionage group against older versions of Windows.

Vulnerability details

Advisory: SB2017031505 - Multiple vulnerabilities in Microsoft Windows

Vulnerable component: Windows

CVE-ID: CVE-2017-0005

CVSSv3 score: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:H/RL:O/RC:C

CWE-ID: CWE-119 - Memory corruption

Description:

The vulnerability allows a local attacker to gain elevated privileges on the target system.

The weakness exists due to improper handling of objects in memory by Windows Graphics Device Interface (GDI). A local attacker can run a specially crafted application, gain elevated privileges and execute arbitrary code on the affected system.

Successful exploitation of the vulnerability may result in arbitrary code execution on the vulnerable system.

Note: the vulnerability was being actively exploited.

External links:

https://technet.microsoft.com/en-us/library/security/MS17-013
https://www.symantec.com/security_response/vulnerability.jsp?bid=96033&om_rssid=sr-advisories 
https://blogs.technet.microsoft.com/mmpc/2017/03/27/detecting-and-mitigating-elevation-of-privilege-...

About zero-day vulnerabilities

Zero-day vulnerability is an undisclosed vulnerability in software that hackers can exploit to compromise computer programs, gain unauthorized access to sensitive data, penetrate networks, etc. We consider vulnerability a zero-day when there is no solution provided from software vendor and the vulnerability is being actively exploited by malicious actors.

Zero-day candidate is a potential zero-day vulnerability in software which might have been used in targeted attacks, however there is no evidence to support this suggestion.