Title: F-Secure BlackLight 2.2.1092 Local Privilege Escalation Vulnerability
Advisory ID: ZSL-2011-5038
Type: Local
Impact: Privilege Escalation
Risk: (2/5)
Release Date: 14.08.2011

Summary

F-Secure BlackLight is a tool that detects files, folders and processes hidden from the user and other programs. BlackLight is also able to remove hidden malware by renaming them.

Description

The rootkit eliminator is vulnerable to an elevation of privileges vulnerability which can be used by a simple user that can change the executable file with a binary of choice. The vulnerability exist due to the improper permissions, with the 'C' flag (change/write) for the 'Everyone' group, for the 'fsbl.exe' binary file.

Vendor

F-Secure Corporation - http://www.f-secure.com

Affected Version

2.2.1092

Tested On

Microsoft Windows XP Professional SP3 (EN)

Vendor Status

[10.08.2011] Vulnerability discovered.
[10.08.2011] Initial contact with the vendor with sent details.
[10.08.2011] Auto-reply from vendor that message is received.
[13.08.2011] No reply from vendor.
[14.08.2011] Public advisory released.
[23.08.2011] After cooperating with the vendor and detailed analysis it is concluded that the vulnerability is void.

PoC

fsecure_pe.txt

Credits

Vulnerability discovered by Gjoko Krstic - <gjoko@zeroscience.mk>

References

[1] http://packetstormsecurity.org/files/104021
[2] http://www.securityfocus.com/bid/49159
[3] http://securityreason.com/exploitalert/10733
[4] http://www.vfocus.net/art/20110817/9344.html

Changelog

[14.08.2011] - Initial release
[16.08.2011] - Added reference [1], [2] and [3]
[18.08.2011] - Added reference [4]
[23.08.2011] - Added vendor status

Contact

Zero Science Lab

Web: http://www.zeroscience.mk
e-mail: lab@zeroscience.mk