CVE-2017-12840 Information

Description

A kernel driver namely DLMFENC.sys bundled with the DESLock+ client application 4.8.16 and earlier contains a locally exploitable heap based buffer overflow in the handling of an IOCTL message of type 0x0FA4204. The vulnerability is present due to the kernel driver failing to allocate sufficient memory on the kernel heap to contain a user supplied string as such the string is copied into a buffer of constant size (0x1000-bytes) and thus an overflow condition results. Access to the kernel driver is permitted through an obfuscated interface whereby bytes of user supplied message are \authenticated\ via an obfuscation routine employing a linear equation.

CVSS Vector

CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Reference

https://www.trustwave.com/Resources/Security-Advisories/Advisories/TWSL2017-016/?fid=9946

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

7.8