CVE-2022-47929: traffic control noqueue no problem?
USER namespaces power the functionality of our favorite tools such as docker, podman, and kubernetes. We wrote about Linux namespaces back in June and explained them like this:
Most of the namespaces are uncontroversial, like the UTS namespace which allows the host system to hide its hostname and time. Others are complex but straightforward - NET and NS (mount) namespaces are known to be hard to wrap your head around. Finally, there is this very special, very curious USER namespace. USER namespace is special since it allows the - typically unprivileged owner to operate as "root" inside it. It's a foundation to having tools like Docker to not operate as true root, and things like rootless containers.
Due to its nature, allowing unprivileged users access to USER namespace always carried a great security risk. With its help the unprivileged user can in fact run code that typically requires root. This code is often under-tested and buggy. Today we will look into one such case where USER namespaces are leveraged to exploit a kernel bug that can result in an unprivileged denial of service attack.
Enter Linux Traffic Control queue disciplines
In 2019, we were exploring leveraging Linux Traffic Control's queue Continue reading
MacOS Ventura 13.1 Breaks Wireshark
If you recently updated your Mac to Ventura 13.1 or 13.2, and you had installed Wireshark previously, then you may be having some trouble. If you open Wireshark, you will likey see the message “You don’t have permission to capture on local interfaces” and “You can fix this by installing ChmodBPF“. Even after installing this […]
The post MacOS Ventura 13.1 Breaks Wireshark appeared first on Packet Pushers.
Hiding Malicious Packets Behind LLC SNAP Header
A random tweet1 pointed me to Vulnerability Note VU#855201 that documents four vulnerabilities exploiting a weird combination of LLC and VLAN headers can bypass layer-2 security on most network devices.
Before anyone starts jumping up and down – even though the VLAN header is mentioned, this is NOT VLAN hopping.
The security researcher who found the vulnerability also provided an excellent in-depth description focused on the way operating systems like Linux and Windows handle LLC-encapsulated IP packets. Here’s the CliffNotes version focused more on the hardware switches. Even though I tried to keep it simple, you might want to read the History of Ethernet Encapsulation before moving on.
I’m still bitter about Slammer
Today is the 20th anniversary of the Slammer worm. I'm still angry over it, so I thought I'd write up my anger. This post will be of interest to nobody, it's just me venting my bitterness and get off my lawn!!
Back in the day, I wrote "BlackICE", an intrusion detection and prevention system that ran as both a desktop version and a network appliance. Most cybersec people from that time remember it as the desktop version, but the bulk of our sales came from the network appliance.
The network appliance competed against other IDSs at the time, such as Snort, an open-source product. For much the cybersec industry, IDS was Snort -- they had no knowledge of how intrusion-detection would work other than this product, because it was open-source.
My intrusion-detection technology was radically different. The thing that makes me angry is that I couldn't explain the differences to the community because they weren't technical enough.
When Slammer hit, Snort and Snort-like products failed. Mine succeeded extremely well. Yet, I didn't get the credit for this.
The first difference is that I used a custom poll-mode driver instead of interrupts. This the now the norm in the industry, such Continue reading
Investing in security to protect data privacy
If you’ve made it to 2023 without ever receiving a notice that your personal information was compromised in a security breach, consider yourself lucky. In a best case scenario, bad actors only got your email address and name – information that won’t cause you a huge amount of harm. Or in a worst-case scenario, maybe your profile on a dating app was breached and intimate details of your personal life were exposed publicly, with life-changing impacts. But there are also more hidden, insidious ways that your personal data can be exploited. For example, most of us use an Internet Service Provider (ISP) to connect to the Internet. Some of those ISPs are collecting information about your Internet viewing habits, your search histories, your location, etc. – all of which can impact the privacy of your personal information as you are targeted with ads based on your online habits.
You also probably haven’t made it to 2023 without hearing at least something about Internet privacy laws around the globe. In some jurisdictions, lawmakers are driven by a recognition that the right to privacy is a fundamental human right. In other locations, lawmakers are passing laws to address the harms their citizens Continue reading
Armed to Boot: an enhancement to Arm’s Secure Boot chain
Over the last few years, there has been a rise in the number of attacks that affect how a computer boots. Most modern computers use a specification called Unified Extensible Firmware Interface (UEFI) that defines a software interface between an operating system (e.g. Windows) and platform firmware (e.g. disk drives, video cards). There are security mechanisms built into UEFI that ensure that platform firmware can be cryptographically validated and boot securely through an application called a bootloader. This firmware is stored in non-volatile SPI flash memory on the motherboard, so it persists on the system even if the operating system is reinstalled and drives are replaced.
This creates a ‘trust anchor’ used to validate each stage of the boot process, but, unfortunately, this trust anchor is also a target for attack. In these UEFI attacks, malicious actions are loaded onto a compromised device early in the boot process. This means that malware can change configuration data, establish persistence by ‘implanting’ itself, and can bypass security measures that are only loaded at the operating system stage. So, while UEFI-anchored secure boot protects the bootloader from bootloader attacks, it does not protect the UEFI firmware itself.
Kubernetes Security And Networking 2: Getting Started With Role-Based Access Control (RBAC) – Video
Role-Based Access Control, or RBAC, lets you set permissions around who can access a system and at what level. RBAC is basic, but essential, security function. This video looks at RBAC for Kubernetes from two perspectives: in native Kubernetes and in platforms such as Azure Active Directory. Host Michael Levan brings his background in system […]
The post Kubernetes Security And Networking 2: Getting Started With Role-Based Access Control (RBAC) – Video appeared first on Packet Pushers.
Kubernetes Security And Networking 1: Why Security Matters And Course Overview
This course looks at securing Kubernetes, with an emphasis, though not exclusively, on network security. Topics we’ll cover in the series include: Role-based access control Securing control planes and worker nodes API security and policy management Dealing with vulnerabilities Security capabilities of a service mesh Security-enabled Container Network Interfaces (CNIs) Securing the ingress controller Scanning […]
The post Kubernetes Security And Networking 1: Why Security Matters And Course Overview appeared first on Packet Pushers.
Infrastructure Privacy Live Webinar
I’m teaching a three-hour webinar on infrastructure privacy this coming Friday. From the description—
Privacy is important to every IT professional, including network engineers—but there is very little training oriented towards anyone other than privacy professionals. This training aims to provide a high-level overview of privacy and how privacy impacts network engineers. Information technology professionals are often perceived as “experts” on “all things IT,” and hence are bound to face questions about the importance of privacy, and how individual users can protect their privacy in more public settings.
There is a recording for anyone who registers.
CIO Week 2023 recap
This post is also available in 日本語, 简体中文, and Español.
In our Welcome to CIO Week 2023 post, we talked about wanting to start the year by celebrating the work Chief Information Officers do to keep their organizations safe and productive.
Over the past week, you learned about announcements addressing all facets of your technology stack – including new services, betas, strategic partnerships, third party integrations, and more. This recap blog summarizes each announcement and labels what capability is generally available (GA), in beta, or on our roadmap.
We delivered on critical capabilities requested by our customers – such as even more comprehensive phishing protection and deeper integrations with the Microsoft ecosystem. Looking ahead, we also described our roadmap for emerging technology categories like Digital Experience Monitoring and our vision to make it exceedingly simple to route traffic from any source to any destination through Cloudflare’s network.
Everything we launched is designed to help CIOs accelerate their pursuit of digital transformation. In this blog, we organized our announcement summaries based on the three feelings we want CIOs to have when they consider partnering with Cloudflare:
- CIOs now have a simpler roadmap to Zero Trust and SASE: We announced Continue reading
Hedge 161: Going Dark with Geoff Huston
Encrypt everything! Now! We don’t often do well with absolutes like this in the engineering world–we tend to focus on “get it down,” and not to think very much about the side effects or unintended consequences. What are the unintended consequences of encrypting all traffic all the time? Geoff Huston joins Tom Ammon and Russ White to discuss the problems with going dark.
API-based email scanning
The landscape of email security is constantly changing. One aspect that remains consistent is the reliance of email as the beginning for the majority of threat campaigns. Attackers often start with a phishing campaign to gather employee credentials which, if successful, are used to exfiltrate data, siphon money, or perform other malicious activities. This threat remains ever present even as companies transition to moving their email to the cloud using providers like Microsoft 365 or Google Workspace.
In our pursuit to help build a better Internet and tackle online threats, Cloudflare offers email security via our Area 1 product to protect all types of email inboxes - from cloud to on premise. The Area 1 product analyzes every email an organization receives and uses our threat models to assess if the message poses risk to the customer. For messages that are deemed malicious, the Area 1 platform will even prevent the email from landing in the recipient's inbox, ensuring that there is no chance for the attempted attack to be successful.
We try to provide customers with the flexibility to deploy our solution in whatever way they find easiest. Continuing in this pursuit to make our solution as turnkey as Continue reading
Expanding our Microsoft collaboration: proactive and automated Zero Trust security for customers
As CIOs navigate the complexities of stitching together multiple solutions, we are extending our partnership with Microsoft to create one of the best Zero Trust solutions available. Today, we are announcing four new integrations between Azure AD and Cloudflare Zero Trust that reduce risk proactively. These integrated offerings increase automation allowing security teams to focus on threats versus implementation and maintenance.
What is Zero Trust and why is it important?
Zero Trust is an overused term in the industry and creates a lot of confusion. So, let's break it down. Zero Trust architecture emphasizes the “never trust, always verify” approach. One way to think about it is that in the traditional security perimeter or “castle and moat” model, you have access to all the rooms inside the building (e.g., apps) simply by having access to the main door (e.g., typically a VPN). In the Zero Trust model you would need to obtain access to each locked room (or app) individually rather than only relying on access through the main door. Some key components of the Zero Trust model are identity e.g., Azure AD (who), apps e.g., a SAP instance or a custom Continue reading
Email Link Isolation: your safety net for the latest phishing attacks
Email is one of the most ubiquitous and also most exploited tools that businesses use every single day. Baiting users into clicking malicious links within an email has been a particularly long-standing tactic for the vast majority of bad actors, from the most sophisticated criminal organizations to the least experienced attackers.
Even though this is a commonly known approach to gain account access or commit fraud, users are still being tricked into clicking malicious links that, in many cases, lead to exploitation. The reason is simple: even the best trained users (and security solutions) cannot always distinguish a good link from a bad link.
On top of that, securing employees' mailboxes often results in multiple vendors, complex deployments, and a huge drain of resources.
Email Link Isolation turns Cloudflare Area 1 into the most comprehensive email security solution when it comes to protecting against phishing attacks. It rewrites links that could be exploited, keeps users vigilant by alerting them of the uncertainty around the website they’re about to visit, and protects against malware and vulnerabilities through the user-friendly Cloudflare Browser Isolation service. Also, in true Cloudflare fashion, it’s a one-click deployment.
Protecting against deceptive links
With more than a couple Continue reading
How Cloudflare Area 1 and DLP work together to protect data in email
Threat prevention is not limited to keeping external actors out, but also keeping sensitive data in. Most organizations do not realize how much confidential information resides within their email inboxes. Employees handle vast amounts of sensitive data on a daily basis, such as intellectual property, internal documentation, PII, or payment information and often share this information internally via email making email one of the largest locations confidential information is stored within a company. It comes as no shock that organizations worry about protecting the accidental or malicious egress of sensitive data and often address these concerns by instituting strong Data Loss Prevention policies. Cloudflare makes it easy for customers to manage the data in their email inboxes with Area 1 Email Security and Cloudflare One.
Cloudflare One, our SASE platform that delivers network-as-a-service (NaaS) with Zero Trust security natively built-in, connects users to enterprise resources, and offers a wide variety of opportunities to secure corporate traffic, including the inspection of data transferred to your corporate email. Area 1 email security, as part of our composable Cloudflare One platform, delivers the most complete data protection for your inbox and offers a cohesive solution when including additional services, such as Data Loss Continue reading
How Cloudflare can help stop malware before it reaches your app
Let’s assume you manage a job advert site. On a daily basis job-seekers will be uploading their CVs, cover letters and other supplementary documents to your servers. What if someone tried to upload malware instead?
Today we’re making your security team job easier by providing a file content scanning engine integrated with our Web Application Firewall (WAF), so that malicious files being uploaded by end users get blocked before they reach application servers.
Enter WAF Content Scanning.
If you are an enterprise customer, reach out to your account team to get access.
Making content scanning easy
At Cloudflare, we pride ourselves on making our products very easy to use. WAF Content Scanning was built with that goal in mind. The main requirement to use the Cloudflare WAF is that application traffic is proxying via the Cloudflare network. Once that is done, turning on Content Scanning requires a single API call.
Once on, the WAF will automatically detect any content being uploaded, and when found, scan it and provide the results for you to use when writing WAF Custom Rules or reviewing security analytics dashboards.
The entire process runs inline with your HTTP traffic and requires no change to your Continue reading
DoS Attack Using Spanning Tree Protocol
The Spanning Tree Protocol (STP) is a network protocol that builds a loop-free logical topology […]
The post DoS Attack Using Spanning Tree Protocol first appeared on Brezular's Blog.
Should ‘Chrome Enhanced Protection’ Be The Default ?
The strongest level of Safe Browsing protection Google Chrome has to offer
Hedge 158: The State of DDoS with Roland Dobbins
DDoS attacks continue to be a persistent threat to organizations of all sizes and in all markets. Roland Dobbins joins Tom Ammon and Russ White to discuss current trends in DDoS attacks, including the increasing scope and scale, as well as the shifting methods used by attackers.