CVE-2015-5697: Infoleak
In the md driver (drivers/md/md.c) of the Linux kernel it’s possible to request a bitmap file for a device using getbitmapfile(), which uses kmalloc(). When bitmap is disabled, only the first byte of the buffer is initialized to zero, and then the whole buffer is copied in user space. It's possible to read up to 4095 bytes of kernel space memory from user space. This results in local kernel information leak.
Upstream patch: http://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/?id=77ba0569d4c8389c0a2162ab0c7c16a6f3b199e4
CVE assignment: http://seclists.org/oss-sec/2015/q3/235
Other sources
The getbitmapfile function in drivers/md/md.c in the Linux kernel before 4.1.6 does not initialize a certain bitmap data structure, which allows local users to obtain sensitive information from kernel memory via a GETBITMAPFILE ioctl call.
— Launchpad
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the vulnerability ID of this vulnerability?
The vulnerability ID is CVE-2015-5697.
What is the severity of CVE-2015-5697?
The severity of CVE-2015-5697 is low.
What is the affected software for CVE-2015-5697?
The affected software for CVE-2015-5697 includes the Linux kernel versions before 4.1.6.
How can a local user exploit CVE-2015-5697?
A local user can exploit CVE-2015-5697 by making a GET_BITMAP_FILE ioctl call to obtain sensitive information from kernel memory.
Are there any remediation measures for CVE-2015-5697?
Yes, the remedy for CVE-2015-5697 is to update the Linux kernel to version 4.1.6 or later.