Vulnerability in Linux kernel could let hackers remotely take over systems

Heap overflow attacks can exploit TIPC module in all common Linux distributions

Linux within a screen full of code

Security researchers have discovered a heap overflow vulnerability in the Transparent Inter-Process Communication (TIPC) module of the kernel of Linux operating systems. Hackers could exploit the vulnerability locally or remotely within a network to gain kernel privileges.

Researchers at SentinelLabs said the vulnerable TIPC module is included in all common Linux distributions but the user must load it to activate the protocol. By exploiting the vulnerability, attackers can compromise the entire system, potentially leading to grave consequences. 

TIPC is a protocol that enables the nodes in a cluster to communicate efficiently while remaining fault-tolerant. The protocol is implemented in a kernel module that is included in all common Linux distributions. When loaded by a user, it can be used as a socket and configured as an unprivileged user on an interface with netlink (or with the userspace tool tipc, which makes these netlink calls).

In September 2020, a new user message type called MSG_CRYPTO was introduced. This enables the sending and exchanging of cryptographic keys, which is the origin of the flaw. 

The possibility of configuration starting from an unprivileged local level and the risk of exploitation from a distance make this a hazardous weak point for all those who use affected systems in their networks. It is particularly worrying that an attacker who exploited this vulnerability could execute arbitrary code within the kernel, potentially resulting in outsiders completely compromising the system.

Related Resource

ITSM workflow handbook: No more "If only IT could do X"

What you need to deliver resilient AI-powered service operations that delight employees

Whitepaper front coverFree Download

“As for the data being overwritten, at first glance it may look like the overflow will have uncontrolled data, since the actual message size used to allocate the heap location is verified,” said researchers.

“However, a second look at the message validation function shows that it only checks that the message size in the header is within the bounds of the actual packet. That means that an attacker could create a 20-byte packet and set the message size to 10 bytes without failing the check.”

On October 19, SentinelLabs reported the findings. In cooperation with the Linux Foundation and one of the TIPC managers, the security researchers created a patch that has been available since October 29th and has been available in current Linux versions (after 5.15) since October 31st.

As the vulnerability was discovered within a year of its introduction to the code base, TIPC users should check whether their Linux kernel version is between 5.10-rc1 and 5.15 and, if necessary, update it. 

As of this writing, SentinelOne has not found any evidence of cyber criminals’ successful misuse of the protocol.

Featured Resources

How virtual desktop infrastructure enables digital transformation

Challenges and benefits of VDI

Free download

The Okta digital trust index

Exploring the human edge of trust

Free download

Optimising workload placement in your hybrid cloud

Deliver increased IT agility with the cloud

Free Download

Modernise endpoint protection and leave your legacy challenges behind

The risk of keeping your legacy endpoint security tools

Download now

Recommended

Red Hat launches Enterprise Linux 9 beta
Linux

Red Hat launches Enterprise Linux 9 beta

3 Nov 2021
IAR Systems and Secure Thingz partner to streamline Azure IoT migration
Microsoft Azure

IAR Systems and Secure Thingz partner to streamline Azure IoT migration

19 Oct 2021
Microsoft makes Windows Subsystem for Linux a Windows 11 app
Linux

Microsoft makes Windows Subsystem for Linux a Windows 11 app

12 Oct 2021
Best Linux distros 2021
operating systems

Best Linux distros 2021

11 Oct 2021

Most Popular

Sony pulls out of MWC 2022
Business operations

Sony pulls out of MWC 2022

14 Jan 2022
How to boot Windows 11 in Safe Mode
Microsoft Windows

How to boot Windows 11 in Safe Mode

6 Jan 2022
Dell XPS 15 (2021) review: The best just got better
Laptops

Dell XPS 15 (2021) review: The best just got better

14 Jan 2022