0

Inside the log4j2 vulnerability (CVE-2021-44228)

Yesterday, December 9, 2021, a very serious vulnerability in the popular Java-based logging package Log4j was disclosed. This vulnerability allows an attacker to execute code on a remote server; a so-called Remote Code Execution (RCE). Because of the widespread use of Java and log4j this is likely one of the most serious vulnerabilities on the Internet since both Heartbleed and ShellShock.

It is CVE-2021-44228 and affects version 2 of log4j between versions 2.0-beta-9 and 2.14.1. It is not present in version 1 of log4j and is patched in 2.15.0.

In this post we explain the history of this vulnerability, how it was introduced, how Cloudflare is protecting our clients. Details of actual attempted exploitation we are seeing blocked by our firewall service are in a separate blog post.

Cloudflare uses some Java-based software and our teams worked to ensure that our systems were not vulnerable or that this vulnerability was mitigated. In parallel, we rolled out firewall rules to protect our customers.

But, if you work for a company that is using Java-based software that uses log4j you should immediately read the section on how to mitigate and protect your systems before reading the rest.

Continue reading

0

Technology Short Take 149

Welcome to Technology Short Take #149! I’ll have one more Technology Short Take in 2021, scheduled for three weeks from now (on the last day of the year!). For now, though, I have a small collection of articles and links for your reading pleasure—not as many as I usually include in a Technology Short Take, but better than nothing at all (I hope!). Enjoy!

Networking

• Thomas Graf recently shared how eBPF will eliminate sidecars in service mesh architectures (he also announces the Cilium Service Mesh beta in the same post). I have many thoughts here—but I will reserve those thoughts until I’ve had time to do a bit more reading and research.
• Ivan tackles the topic of CI/CD and testing in network automation.

Security

• Dan Lorenc dives deep into Fulcio.
• From the Not Surprised Department, some folks are starting to take a harder look at the timelines for security patches for older versions of macOS compared to newer versions. Ars Technica has a write-up on what’s been observed so far.
• Rory McCune of Aqua shares some new security-related features in the Kubernetes 1.23 release.

Cloud Computing/Cloud Management

• I shared this via Twitter as well, but this is Continue reading

0

Heavy Networking 610: Network Automation With Nautobot

On today's Heavy Networking we discuss a Nautobot, an open-source software tool that can serve as a source of truth for network automation. We explore how Nautobot works, what it's used for, how it ties in with Python and Ansible, major features, and more.

0

Is Disaggregation Going to Be Cord Cutting for the Enterprise?

There’s a lot of talk in the networking industry around disaggregation. The basic premise is that by decoupling the operating system from the hardware you can gain the freedom to run the devices you want from any vendor with the software that does what you want it to do. You can standardize or mix-and-match as you see fit. You gain the ability to direct the way your network works and you control how things will be going forward.

To me it sounds an awful lot like the trend of “cutting the cord” or unsubscribing from cable TV service and picking and choosing how you want to consume your content. Ten years ago the idea of getting rid of your cable TV provider was somewhat crazy. In 2021 it seems almost a given that you no long need to rely on your cable provider for entertainment. However, just like with the landscape of the post-cable cutting world, I think disaggregation is going to lead to a vastly different outcome than expected.

TNSTAAFL

Let’s get one thing out of the way up front: This idea of “freedom” when it comes to disaggregation and cord cutting is almost always about money. Yes, you Continue reading

0

Hedge 111: Machine Learning and Security with Micah Mussler

Machine Learning (ML) and Artificial Intelligence (AI) are all the rage in the network engineering world. Where might these technologies be useful, as opposed to mere hype? The two most obvious areas where AI and ML would be useful are failure reaction and security. Micah Mussler joins Tom Ammon and Russ White to discuss the possibilities of using AI and/or ML in the broader security market—and focusing in on the network.

download

0

Cloudflare One helps optimize user connectivity to Microsoft 365

We are excited to announce that Cloudflare has joined the Microsoft 365 Networking Partner Program (NPP).  Cloudflare One, which provides an optimized path for traffic from Cloudflare customers to Microsoft 365, recently qualified for the NPP by demonstrating that on-ramps through Cloudflare’s network help optimize user connectivity to Microsoft.

Connecting users to the Internet on a faster network

Customers who deploy Cloudflare One give their team members access to the world’s fastest network, on average, as their on-ramp to the rest of the Internet. Users connect from their devices or offices and reach Cloudflare’s network in over 250 cities around the world. Cloudflare’s network accelerates traffic to its final destination through a combination of intelligent routing and software improvements.

We’re also excited that, in many cases, the final destination that a user visits already sits on Cloudflare’s network. Cloudflare serves over 28M HTTP requests per second, on average, for the millions of customers who secure their applications on our network. When those applications do not run on our network, we can rely on our own global private backbone and our connectivity with over 10,000 networks globally to connect the user.

For Microsoft 365 traffic, we focus on breaking out Continue reading

0

Argo for Packets is Generally Available

What would you say if we told you your IP network can be faster by 10%, and all you have to do is reach out to your account team to make it happen?

Today, we’re announcing the general availability of Argo for Packets, which provides IP layer network optimizations to supercharge your Cloudflare network services products like Magic Transit (our Layer 3 DDoS protection service), Magic WAN (which lets you build your own SD-WAN on top of Cloudflare), and Cloudflare for Offices (our initiative to provide secure, performant connectivity into thousands of office buildings around the world).

If you’re not familiar with Argo, it’s a Cloudflare product that makes your traffic faster. Argo finds the fastest, most available path for your traffic on the Internet. Every day, Cloudflare carries trillions of requests, connections, and packets across our network and the Internet. Because our network, our customers, and their end users are well distributed globally, all of these requests flowing across our infrastructure paint a great picture of how different parts of the Internet are performing at any given time. Cloudflare leverages this picture to ensure that your traffic takes the fastest path through our infrastructure.

Previously, Argo optimized traffic at Continue reading

0

Cloudflare announces integrations with MDM companies

At Cloudflare, we are continuously thinking about ways to make the Internet more secure, more reliable and more performant for consumers and businesses of all sizes. Connecting devices safely to applications is critical for the safety of enterprise applications and for the peace of mind of a CIO.

Last January, we launched our Zero Trust platform, Cloudflare for Teams, that protects users, their devices, and their data by replacing legacy security perimeters with Cloudflare’s global edge network. Cloudflare for Teams makes security solutions like Zero Trust Network Access and Secure Web Gateway more accessible, for all companies, regardless of size, scale, or resources. This means building products that are more user-friendly, easier to deploy, and less cumbersome to manage.

The Cloudflare WARP agent encrypts traffic from devices to Cloudflare’s network, and many customers use it as a critical component to extend default-deny controls to where their users are. Today, Cloudflare is rolling out richer documentation on how to deploy WARP with these partners, so your administrators have a streamlined, easy-to-follow process to enroll your entire device fleet.

And we’re excited to announce new integrations with mobile device management vendors Microsoft Intune, Ivanti, JumpCloud, Kandji, and Hexnode to make it Continue reading

0

Cloudflare Agent — Seamless Deployment at Scale

A year ago we launched WARP for Desktop to give anyone a fast, private on-ramp to the Internet. For our business customers, IT and security administrators can also use that same agent and enroll the devices in their organization into Cloudflare for Teams. Once enrolled, their team members have an accelerated on-ramp to the Internet where Cloudflare can also provide comprehensive security filtering from network firewall functions all the way to remote browser isolation.

When we launched last year, we supported the broadest possible deployment mechanisms with a simple set of configuration options to get your organization protected quickly. We focused on helping organizations keep users and data safe with HTTP and DNS filtering from any location. We started with support for Mac, Windows, iOS, and Android.

Since that launch, thousands of organizations have deployed the agent to secure their team members and endpoints. We’ve heard from customers who are excited to expand their rollout, but need more OS support and great control over the configuration.

Today we are excited to announce our zero trust agent now has feature parity across all major platforms. Beyond that, you can control new options to determine how traffic is routed and your administrators Continue reading

0

Introducing Cloudflare Domain Protection — Making Domain Compromise a Thing of the Past

Everything on the web starts with a domain name. It is the foundation on which a company’s online presence is built. If that foundation is compromised, the damage can be immense.

As part of CIO Week, we looked at all the biggest risks that companies continue to face online, and how we could address them. The compromise of a domain name remains one of the greatest. There are many ways in which a domain may be hijacked or otherwise compromised, all the way up to the most serious: losing control of your domain name altogether.

You don’t want it to happen to you. Imagine not just losing your website, but all your company’s email, a myriad of systems tied to your corporate domain, and who knows what else. Having an attacker compromise your corporate domain is the stuff of nightmares for every CIO. And, if you’re a CIO and it’s not something you’re worrying about, know that we literally surveyed every other domain registrar and were so unsatisfied with their security practices we needed to launch our own.

But, now that we have, we want to make domain compromise something that should never, ever happen again. For that reason, we’re Continue reading

0

Cumulus Part X – VXLAN EVPN and MLAG

In this post, we take a look at the interaction of MLAG with an EVPN based VXLAN fabric on Cumulus Linux.

0

Cumulus Part IX – Understanding VXLAN EVPN Route-Target control

In this post, we look at how route-targets extended communities can be used to control VXLAN BGP EVPN routes in Cumulus Linux.

0

Cumulus Basics Part VIII – VXLAN symmetric routing and multi-tenancy

In this post, we look at VXLAN routing with symmetric IRB and multi-tenancy on Cumulus Linux.

0

Cumulus Basics Part VII – VXLAN routing – asymmetric IRB

In this post, we look at VXLAN routing with asymmetric IRB on Cumulus Linux.

0

Cumulus Basics Part VI – VXLAN L2VNIs with BGP EVPN

In this post, we introduce BGP EVPN and a VXLAN fabric in Cumulus Linux, with L2VNIs.

0

Cumulus Basics Part V – BGP unnumbered

In this post, we’ll look at BGP unnumbered on Cumulus Linux.

0

Cumulus Basics Part IV – BGP introduction

In this post, we introduce BGP on Cumulus Linux.

0

CVE-2021-44228 – Log4j RCE 0-day mitigation

A zero-day exploit affecting the popular Apache Log4j utility (CVE-2021-44228) was made public on December 9, 2021 that results in remote code execution (RCE).

This vulnerability is actively being exploited and anyone using Log4j should update to version 2.15.0 as soon as possible. The latest version can already be found on the Log4j download page.

If updating to the latest version is not possible, customers can also mitigate exploit attempts by setting the system property "log4j2.formatMsgNoLookups" to “true”; or by removing the JndiLookup class from the classpath. Java release 8u121 also protects against this remote code execution vector.

Customers using the Cloudflare WAF can also leverage three newly deployed rules to help mitigate any exploit attempts:

Rule ID	Description	Default Action
100514 (legacy WAF) 6b1cc72dff9746469d4695a474430f12 (new WAF)	Log4j Headers	BLOCK
100515 (legacy WAF) 0c054d4e4dd5455c9ff8f01efe5abb10 (new WAF)	Log4j Body	LOG
100516 (legacy WAF) 5f6744fa026a4638bda5b3d7d5e015dd (new WAF)	Log4j URL	LOG

The mitigation has been split across three rules inspecting HTTP headers, body and URL respectively.

Due to the risk of false positives, customers should immediately review Firewall Event logs and switch the Log4j Body and URL rules to BLOCK if none are found. Continue reading

0

Podcast: Ironing Out the BGP Ruffles

After the (in)famous October 2021 Facebook outage, Corey Quinn invited me for another Screaming in the Cloud chat, this time focusing on what went wrong (hint: it wasn’t DNS or BGP).

We also touched on VAX/VMS history, how early CCIE lab exams worked, how BGP started, why there are only 13 root name servers (not really), and the transition from networking being pure magic to becoming a commodity. Hope you’ll enjoy our chat as much as I did.

0

Podcast: Ironing Out the BGP Ruffles

After the (in)famous October 2021 Facebook outage, Corey Quinn invited me for another Screaming in the Cloud chat, this time focusing on what went wrong (hint: it wasn’t DNS or BGP).

We also touched on VAX/VMS history, how early CCIE lab exams worked, how BGP started, why there are only 13 root name servers (not really), and the transition from networking being pure magic to becoming a commodity. Hope you’ll enjoy our chat as much as I did.