Pierluigi Paganini April 14, 2017

The Linux remote vulnerability tracked as CVE-2016-10229 poses Linux systems at rick of hack if not patched.

A Linux kernel vulnerability, trackers as CVE-2016-10229, potentially allows attackers to remotely take over a vulnerable system (i.e. Servers, desktops, IoT devices and mobile devices).

“udp.c in the Linux kernel before 4.5 allows remote attackers to execute arbitrary code via UDP traffic that triggers an unsafe second checksum calculation during execution of a recv system call with the MSG_PEEK flag.” reads the description of the flaw published by the NDV.

The CVE-2016-10229 flaw expose systems to attacks via UDP traffic, according to the experts. the attackers can potential hack a system running a software receiving data through the system call recv() with the MSG_PEEK flag set on. This means that attackers would send to the target specifically crafted packets that trigger the CVE-2016-10229 flaw by forcing a second checksum operation on the incoming data. In this way, the attacker can execute malicious code within the kernel with root privileges, fortunately the issue is hard to exploit as explained by the popular Google Project Zero hacker Tavis Ormandy.

I'm as confused as you are…

— Tavis Ormandy (@taviso) April 13, 2017

Common software, like the Nginx web server, set the MSG_PEEK flag on some connections, potentially exposing the system to the attack.

The bug can also be potentially exploited by a local attacker to escalate privileges.

The vulnerability was discovered by the expert from Google Eric Dumazet who explained that the issue dates back the end of 2015 when a small fix was applied to the Linux kernel.

Affected versions are the Kernel versions below 4.5, all the way down to 2.6, are likely at risk, major Linux distribution such as Ubuntu and Debian were distributing fixed builds of the kernel by February this year.

According to Red Hat, it Linux distribution were never affected by the CVE-2016-10229 flaw.

Google has already rolled out security patches for Android that also fixed the CVE-2016-10229 in mobile devices.

“So, in short, yes, there is a remote kernel-level code execution vulnerability in Linux, which sounds like the worst of the very worst, but it is pretty much patched by now – and it appears to be tricky to exploit. It was silently addressed in the kernel source over a year ago, and fixed in updates to machines earlier this year, but only now has it come to wider attention.” reported The Register.

[adrotate banner=”9″]

Pierluigi Paganini

(Security Affairs –  Linux Kernel, CVE-2016-10229)