Trustwave SpiderLabs Security Advisory TWSL2018-007:
Kernel Level Privilege Escalation via AVS in Oracle Solaris 10/11

Published: Currently unpublished 
Version: 1.0

Vendor: Oracle Corporation (https://www.oracle.com/solaris/solaris11/)
Product: Oracle Solaris 10/11
Version affected: <=10/<=11.3

Product description:
Oracle Solaris is the world’s most advanced enterprise operating system. It provides you continuous innovation and delivery, secures your data, simplifies the system and application lifecycle, and includes cloud capabilities in a single, mission-critical platform.

Finding: Privilege Escalation via Kernel Mode Memory Write
Credit: Neil Kettle of Trustwave
CVE: CVE-2018-2892

A local kernel ring0 code execution vulnerability exists in the Oracle Solaris AVS kernel component permitting arbitrary code execution and thus privilege escalation. The issue is the result of a signedness bug in the bounds checking of the 'SDBC_TEST_INIT' ioctl code sent to the '/dev/sdbc' device. The result is a call to copyin() with a user controllable destination pointer and length thereby facilitating an arbitrary kernel memory overwrite and thus arbitrary code execution in the context of the kernel.

Remediation Steps:
For Oracle Solaris 10 installations, patches will be distributed via Oracle's extended support offering.  Oracle 11.3 installations can be patched with Oracle July 2018 Critical Patch Update (CPU) applied.  

Revision History:
03/13/2018 - Vulnerability disclosed to vendor
07/17/2018 - Patch released by vendor
07/24/2018 - Advisory published


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