Zero-day vulnerability in Microsoft Internet Explorer

Memory corruption
CVE-2011-1255

According to experts from M86, this vulnerability was exploited in targeted attacks before the official patch release from Microsoft.

Vulnerability details

Advisory: SB2011061403 - Multiple vulnerabilities in Microsoft Internet Explorer

Vulnerable component: Microsoft Internet Explorer

CVE-ID: CVE-2011-1255

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-119 - Memory corruption

Description:

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

The weakness exists due to boundary error related to time element when Internet Explorer attempts to access objects that have not been correctly initialized or have been deleted. A remote attacker can create a specially crafted Web site, trick the victim into visiting it, trigger memory corruption and execute arbitrary code with privileges of the current user.

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

Note: According to experts from M86, the vulnerability was exploited in targeted attacks before the official patch release from Microsoft.

Public Exploits:

- Microsoft Internet Explorer - Time Element Memory Corruption (MS11-050) [Exploit-DB]

External links:

http://news.softpedia.com/news/Recently-Patched-IE-Flaw-Exploited-as-Zero-Day-208646.shtml
http://digcert.com/docs/symantec/symantec_report_2012.htm
http://securityaffairs.co/wordpress/44749/cyber-crime/operation-dust-storm.html
https://technet.microsoft.com/en-us/library/security/ms11-050.aspx

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.