Thursday, April 18, 2024

New Linux Bug in Netfilter Firewall Module Lets Attackers Gain Root Access

A newly disclosed security flaw in the Linux kernel could be leveraged by a local adversary to gain elevated privileges on vulnerable systems to execute arbitrary code, escape containers, or induce a kernel panic.

Linux Bug in Netfilter Leads To Root

Tracked as CVE-2022-25636 (CVSS score: 7.8), the vulnerability impacts Linux kernel versions 5.4 through 5.6.10 and is a result of a heap out-of-bounds write in the netfilter subcomponent in the kernel. The issue was discovered by Nick Gregory, a research scientist at Capsule8.

“This flaw allows a local attacker with a user account on the system to gain access to out-of-bounds memory, leading to a system crash or a privilege escalation threat,” Red Hat said in an advisory published on February 22, 2022. Similar alerts have been released by DebianOracle LinuxSUSE, and Ubuntu.

Netfilter is a framework provided by the Linux kernel that enables various networking-related operations, including packet filtering, network address translation, and port translation.

Specifically, CVE-2022-25636 relates to an issue with incorrect handling of the framework’s hardware offload feature that could be weaponized by a local attacker to cause a denial-of-service (DoS) or possibly execute arbitrary code.

“Despite being in code dealing with hardware offload, this is reachable when targeting network devices that don’t have offload functionality (e.g. lo) as the bug is triggered before the rule creation fails.” Gregory said. “Additionally, while nftables requires CAP_NET_ADMIN, we can unshare into a new network namespace to get this as a (normally) unprivileged user.”

“This can be turned into kernel [return-oriented programming]/local privilege escalation without too much difficulty, as one of the values that is written out of bounds is conveniently a pointer to a net_device structure,” Gregory added.

Recommended:  Open Database Leaves Major Chinese ports Exposed to Shipping Chaos

Suggest a change to this article

Go to Cybersecurity Knowledge Base

Got to the Latest Cybersecurity News

Go to Cybersecurity Academy

Go to Homepage

Stay informed of the latest Cybersecurity trends, threats and developments. Sign up for our Weekly Cybersecurity Newsletter Today.

Remember, CyberSecurity Starts With You!

  • Globally, 30,000 websites are hacked daily.
  • 64% of companies worldwide have experienced at least one form of a cyber attack.
  • There were 20M breached records in March 2021.
  • In 2020, ransomware cases grew by 150%.
  • Email is responsible for around 94% of all malware.
  • Every 39 seconds, there is a new attack somewhere on the web.
  • An average of around 24,000 malicious mobile apps are blocked daily on the internet.
Bookmark
ClosePlease login
Share the word, let's increase Cybersecurity Awareness as we know it
- Sponsored -

Sponsored Offer

Unleash the Power of the Cloud: Grab $200 Credit for 60 Days on DigitalOcean!

Digital ocean free 200

Discover more infosec

User Avatar
Steven Black (n0tst3)
Hello! I'm Steve, an independent security researcher, and analyst from Scotland, UK. I've had an avid interest in Computers, Technology and Security since my early teens. 20 years on, and, it's a whole lot more complicated... I've assisted Governments, Individuals and Organizations throughout the world. Including; US DOJ, NHS UK, GOV UK. I'll often reblog infosec-related articles that I find interesting. On the RiSec website, You'll also find a variety of write-ups, tutorials and much more!

more infosec reads

Subscribe for weekly updates

explore

more

security