Zero-day vulnerability in Microsoft WordPad

Stack-based buffer overflow
CVE-2008-4841

Known malware:

Exploit: Win32/CVE-2008-4841

Vulnerability details

Advisory: SB2008120902 - Remote code execution in Microsoft Word

Vulnerable component: Microsoft WordPad

CVE-ID: CVE-2008-4841

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-121 - Stack-based buffer overflow

Description:

The vulnerability alows a remote authenticated attacker to execute arbitrary code on the target system.

The weakness exists due to stack overflow when parsing a malicious document. A remote attacker can create a specially crafted Word file containing a malformed list structure, trick the victim into opening it, trigger memory corruption and execute arbitrary code on the target system with privileges of the current user

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

Note: the vulnerability was being actively exploited.

Public Exploits:

- Microsoft Windows Wordpad - '.doc' File Local Denial of Service (PoC) [Exploit-DB]

External links:

https://technet.microsoft.com/library/security/960906
https://technet.microsoft.com/en-us/library/security/ms09-010.aspx
https://www.us-cert.gov/ncas/alerts/TA09-104A
http://www.openwall.com/lists/oss-security/2009/01/21/9
https://www.suse.com/security/cve/CVE-2008-4841
http://contagiodump.blogspot.com/2010/04/cve-2008-4841-wordpad-text-converter.html

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.