|
Linux Kernel "splice()" O_APPEND Bypass and I915 Privilege Escalation
|
|
Secunia Advisory:
|
SA32320
|
|
|
Release Date:
|
2008-10-20
|
|
Last Update:
|
2008-10-23
|
|
Popularity:
|
1,892 views
|
|
|
Critical:
|
Less critical
|
|
Impact:
|
Security Bypass
Privilege escalation
|
|
Where:
|
Local system
|
|
Solution Status:
|
Vendor Patch
|
|
| OS: | Linux Kernel 2.6.x
|
|
|
Subscribe:
|
Instant alerts on relevant vulnerabilities 
|
|
| CVE reference: | CVE-2008-3831
CVE-2008-4554
|
|
Description:
A weakness and a vulnerability have been reported in the Linux kernel, which can be exploited by malicious, local users to bypass certain security restrictions and potentially gain escalated privileges.
1) A vulnerability is caused due to the DRM_I915_HWS_ADDR IOCTL being available to non-root users, which can be exploited to e.g. zero and remap memory locations by sending a specially crafted IOCTL to the driver.
Successful exploitation may allow to execute arbitrary code with escalated privileges, but requires an Intel G33 series or newer chipset.
2) A weakness is caused due to the "do_splice_from()" function in fs/splice.c not honoring the "O_APPEND" flag. This can be exploited by using the "splice()" system call to write to arbitrary locations in a file regardless of the "O_APPEND" setting.
Solution:
Update to version 2.6.25.19, 2.6.26.7, or 2.6.27.3.
Provided and/or discovered by:
1) Olaf Kirch
2) Miklos Szeredi
Changelog:
2008-10-23: Updated advisory to include weakness #2. Updated "Solution" section.
Original Advisory:
http://kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.25.19
http://kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.26.7
http://kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.27.3
|
|
|
Track this Secunia Advisory
|
Customers of the Secunia Vulnerability Intelligence solutions will automatically receive updates when new information regarding this advisory is released.
Read more about our Vulnerability Intelligence solutions and what they can do for you and your company.
|
|
|
About this Secunia Advisory
|
Please note: The information that this Secunia Advisory is based on comes from a third party unless stated otherwise.
Secunia collects, validates, and verifies all vulnerability reports issued by security research groups, vendors, and others.
|
