Zero-day vulnerability in Microsoft Word

Remote code execution
CVE-2006-2492

Known malware:

Mdropper.H Trojan.
SmartTag exploit.

Vulnerability details

Advisory: SB2006061301 - Remote code execution in Microsoft Word

Vulnerable component: Microsoft Word

CVE-ID: CVE-2006-2492

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

CWE-ID: CWE-120 - Buffer overflow

Description:

The vulnerability allows a remote user to execute arbitrary code on the target system.

The weakness is due to buffer overflow. By persuading the victim to open a specially crafted Word file containing a malformed object pointer, a remote attacker can execute arbitrary code.
Successful exploitation of the vulnerability results in arbitrary code execution on the vulnerable system.

Note: this vulnerability was being actively exploited.

External links:

https://technet.microsoft.com/en-us/library/security/ms06-027.aspx
https://blogs.technet.microsoft.com/msrc/2006/05/20/a-quick-check-in-on-the-word-vulnerability/
https://blogs.microsoft.com/microsoftsecure/2011/09/28/targeted-attacks-and-the-need-to-keep-documen...
http://www.networkworld.com/article/2266902/lan-wan/microsoft--rogue--security--software-a-rising-th...
https://www.theguardian.com/technology/blog/2010/apr/26/microsoft-security-intelligence-report
http://www.bcs.org/content/conWebDoc/11820
http://rbach.net/blog/index.php/msft-security-report/
http://garwarner.blogspot.com/2009/04/microsoft-security-intelligence-report.html
https://www.itnews.com.au/news/taiwanese-gang-exploits-microsoft-word-81693
http://www.marketwired.com/press-release/MessageLabs-Intelligence-Targeted-Attack-Report-Criminal-Ri...

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.