Microsoft Internet Explorer Filesystem Elevation of Privilege Vulnerability
Vulnerability Details
This vulnerability allows attackers to escalate privileges on vulnerable installations of Microsoft Internet Explorer. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The specific flaw exists within the handling of junction points in the Favorites folder linked to other folders. An attacker running code in the context of a low-rights Internet Explorer process can set up a junction point in the Favorites folder and then the IE broker process will change access control rights in the targeted folders (which are normally unmodifiable by the low-rights process). An attacker can leverage this vulnerability to execute code under the context of a medium integrity process.
Additional Details
Microsoft has issued an update to correct this vulnerability. More details can be found at:
https://technet.microsoft.com/library/security/MS15-090
Disclosure Timeline
- 2015-02-09 - Vulnerability reported to vendor
- 2015-08-11 - Coordinated public release of advisory
Credit
Ashutosh Mehra (https://twitter.com/ashutoshmehra)
