Manipulate Your Way to the Root of It
One of the nice things about Linux — but by no means the most important — is the enhanced security that comes along with running it. That doesn't mean Linux never runs into security issues, though, and this week, the vulnerability in question centers around a nifty little service called udev.
According to advisories from several distributions, including Fedora, Ubuntu, and SUSE, a bug has been discovered that allows a local or remote user to exploit the udev service in order to gain root access to the system. Specially crafted Netlink messages, if sent to udev, can allow the sender to create a block device file that is globally-writable for an existing block device — that includes the root file system. The attacker can then create or manipulate files in order to gain root access to the system.
udev is a service, not a part of the kernel itself, used by most 2.6 series kernels to dynamically create files and folders — the /dev directory — for input and output from specific devices.
According to the SUSE Security Team's Sebastian Krahmer, who discovered the original bug, a further udev issue has been discovered, involving a function for decoding the path which is vulnerable to an integer overflow, and according to reports, to a heap overflow as well. At this time, it has only been confirmed that this second bug can cause udev to crash, though Fedora's security team has not ruled out the possibility that it may be exploited to obtain root access.
Fixes are in the works for the affected distributions, with some having already pushed updated packages to users while others are in the process. More information is available through security advisories from the relevant distributions, including Ubuntu Security Notice USN-758-1 and FEDORA-2009-3711.
Justin Ryan is a Contributing Editor for Linux Journal.
Fast/Flexible Linux OS Recovery
On Demand Now
In this live one-hour webinar, learn how to enhance your existing backup strategies for complete disaster recovery preparedness using Storix System Backup Administrator (SBAdmin), a highly flexible full-system recovery solution for UNIX and Linux systems.
Join Linux Journal's Shawn Powers and David Huffman, President/CEO, Storix, Inc.
Free to Linux Journal readers.Register Now!
- Download "Linux Management with Red Hat Satellite: Measuring Business Impact and ROI"
- Petros Koutoupis' RapidDisk
- ServersCheck's Thermal Imaging Camera Sensor
- The Italian Army Switches to LibreOffice
- Linux Mint 18
- Oracle vs. Google: Round 2
- The FBI and the Mozilla Foundation Lock Horns over Known Security Hole
- Privacy and the New Math
- Varnish Software's Varnish Massive Storage Engine
Until recently, IBM’s Power Platform was looked upon as being the system that hosted IBM’s flavor of UNIX and proprietary operating system called IBM i. These servers often are found in medium-size businesses running ERP, CRM and financials for on-premise customers. By enabling the Power platform to run the Linux OS, IBM now has positioned Power to be the platform of choice for those already running Linux that are facing scalability issues, especially customers looking at analytics, big data or cloud computing.
￼Running Linux on IBM’s Power hardware offers some obvious benefits, including improved processing speed and memory bandwidth, inherent security, and simpler deployment and management. But if you look beyond the impressive architecture, you’ll also find an open ecosystem that has given rise to a strong, innovative community, as well as an inventory of system and network management applications that really help leverage the benefits offered by running Linux on Power.Get the Guide