Going Keyless Everywhere

Time flies. The Heartbleed vulnerability was discovered just over five and a half years ago. Heartbleed became a household name not only because it was one of the first bugs with its own web page and logo, but because of what it revealed about the fragility of the Internet as a whole. With Heartbleed, one tiny bug in a cryptography library exposed the personal data of the users of almost every website online.

Heartbleed is an example of an underappreciated class of bugs: remote memory disclosure vulnerabilities. High profile examples other than Heartbleed include Cloudbleed and most recently NetSpectre. These vulnerabilities allow attackers to extract secrets from servers by simply sending them specially-crafted packets. Cloudflare recently completed a multi-year project to make our platform more resilient against this category of bug.

For the last five years, the industry has been dealing with the consequences of the design that led to Heartbleed being so impactful. In this blog post we’ll dig into memory safety, and how we re-designed Cloudflare’s main product to protect private keys from the next Heartbleed.

Memory Disclosure

Perfect security is not possible for businesses with an online component. History has shown us that no matter how Continue reading

Delegated Credentials for TLS

Today we’re happy to announce support for a new cryptographic protocol that helps make it possible to deploy encrypted services in a global network while still maintaining fast performance and tight control of private keys: Delegated Credentials for TLS. We have been working with partners from Facebook, Mozilla, and the broader IETF community to define this emerging standard. We’re excited to share the gory details today in this blog post.

Also, be sure to check out the blog posts on the topic by our friends at Facebook and Mozilla!

Deploying TLS globally

Many of the technical problems we face at Cloudflare are widely shared problems across the Internet industry. As gratifying as it can be to solve a problem for ourselves and our customers, it can be even more gratifying to solve a problem for the entire Internet. For the past three years, we have been working with peers in the industry to solve a specific shared problem in the TLS infrastructure space: How do you terminate TLS connections while storing keys remotely and maintaining performance and availability? Today we’re announcing that Cloudflare now supports Delegated Credentials, the result of this work.

Cloudflare’s TLS/SSL features are among the top reasons Continue reading

Nokia’s SOAR Lineup Tackles 5G, IoT Security

What Scary Movies Can Teach Us About Internet Trust

Mad geniuses. Evil dolls. Slow zombies. This Halloween, we’ll see all of these horror film clichés come to life. Sure they’re fun, but are there lessons we can learn from them? What if they could teach us what not to do? We looked at seven scary tropes and what they might teach us about Internet trust.

The call is coming from inside the house.

The phone calls keep coming, each one scarier than the last. Ring. “Are you home alone?” Ring. “Have you locked the doors?” Ring. “Look in the basement.” It’s only then you realize the stalker has been in the house all along.

We lock our doors to make our homes more secure, but we don’t always think about the security of the things we connect to our home networks. An insecure connected device can put your whole network and the devices on it at risk. Meaning, yes, the cybersecurity threat could be coming from inside the house. By protecting your home network, you limit your devices’ exposure to online threats and help mitigate the risk they may pose to others. You can make your network more secure by using encryption, a strong password, and Continue reading

Announcing cfnts: Cloudflare’s implementation of NTS in Rust

Several months ago we announced that we were providing a new public time service. Part of what we were providing was the first major deployment of the new Network Time Security (NTS) protocol, with a newly written implementation of NTS in Rust. In the process, we received helpful advice from the NTP community, especially from the NTPSec and Chrony projects. We’ve also participated in several interoperability events. Now we are returning something to the community: Our implementation, cfnts, is now open source and we welcome your pull requests and issues.

The journey from a blank source file to a working, deployed service was a lengthy one, and it involved many people across multiple teams.

"Correct time is a necessity for most security protocols in use on the Internet. Despite this, secure time transfer over the Internet has previously required complicated configuration on a case by case basis. With the introduction of NTS, secure time synchronization will finally be available for everyone. It is a small, but important, step towards increasing security in all systems that depend on accurate time. I am happy that Cloudflare are sharing their NTS implementation. A diversity of software with NTS support is important for quick Continue reading

Deutsche Telekom Tackles Cyber Theft, Cloud Management

Qualcomm-Backed Particle Banks $40M to Expand IoT Platform

The TLS Post-Quantum Experiment

In June, we announced a wide-scale post-quantum experiment with Google. We implemented two post-quantum (i.e., not yet known to be broken by quantum computers) key exchanges, integrated them into our TLS stack and deployed the implementation on our edge servers and in Chrome Canary clients. The goal of the experiment was to evaluate the performance and feasibility of deployment in TLS of two post-quantum key agreement ciphers.

In our previous blog post on post-quantum cryptography, we described differences between those two ciphers in detail. In case you didn’t have a chance to read it, we include a quick recap here. One characteristic of post-quantum key exchange algorithms is that the public keys are much larger than those used by "classical" algorithms. This will have an impact on the duration of the TLS handshake. For our experiment, we chose two algorithms: isogeny-based SIKE and lattice-based HRSS. The former has short key sizes (~330 bytes) but has a high computational cost; the latter has larger key sizes (~1100 bytes), but is a few orders of magnitude faster.

During NIST’s Second PQC Standardization Conference, Nick Sullivan presented our approach to this experiment and some initial results. Quite accurately, Continue reading

Understanding Kubernetes Security on Docker Enterprise 3.0

This is a guest post by Javier Ramírez, Docker Captain and IT Architect at Hopla Software. You can follow him on Twitter @frjaraur or on Github.

Docker began including Kubernetes with Docker Enterprise 2.0 last year. The recent 3.0 release includes CNCF Certified Kubernetes 1.14, which has many additional security features. In this blog post, I will review Pod Security Policies and Admission Controllers.

What are Kubernetes Pod Security Policies?

Pod Security Policies are rules created in Kubernetes to control security in pods. A pod will only be scheduled on a Kubernetes cluster if it passes these rules. These rules are defined in the  “PodSecurityPolicy” resource and allow us to manage host namespace and filesystem usage, as well as privileged pod features. We can use the PodSecurityPolicy resource to make fine-grained security configurations, including:

• Privileged containers.
• Host namespaces (IPC, PID, Network and Ports).
• Host paths and their permissions and volume types.
• User and group for containers process execution and setuid capabilities inside container.
• Change default containers capabilities.
• Behaviour of Linux security modules.
• Allow host kernel configurations using sysctl.

The Docker Universal Control Plane (UCP) 3.2 provides two Pod Security Policies by default – which is helpful Continue reading

DNS Encryption Explained

The Domain Name System (DNS) is the address book of the Internet. When you visit cloudflare.com or any other site, your browser will ask a DNS resolver for the IP address where the website can be found. Unfortunately, these DNS queries and answers are typically unprotected. Encrypting DNS would improve user privacy and security. In this post, we will look at two mechanisms for encrypting DNS, known as DNS over TLS (DoT) and DNS over HTTPS (DoH), and explain how they work.

Applications that want to resolve a domain name to an IP address typically use DNS. This is usually not done explicitly by the programmer who wrote the application. Instead, the programmer writes something such as fetch("https://example.com/news") and expects a software library to handle the translation of “example.com” to an IP address.

Behind the scenes, the software library is responsible for discovering and connecting to the external recursive DNS resolver and speaking the DNS protocol (see the figure below) in order to resolve the name requested by the application. The choice of the external DNS resolver and whether any privacy and security is provided at all is outside the control of the application. It depends on Continue reading

Nokia Beats ‘Trust and Security’ Drum to Bolster 5G Position

Microsoft Unleashes a Tsunami of IoT Updates

Supporting the latest version of the Privacy Pass Protocol

At Cloudflare, we are committed to supporting and developing new privacy-preserving technologies that benefit all Internet users. In November 2017, we announced server-side support for the Privacy Pass protocol, a piece of work developed in collaboration with the academic community. Privacy Pass, in a nutshell, allows clients to provide proof of trust without revealing where and when the trust was provided. The aim of the protocol is then to allow anyone to prove they are trusted by a server, without that server being able to track the user via the trust that was assigned.

On a technical level, Privacy Pass clients receive attestation tokens from a server, that can then be redeemed in the future. These tokens are provided when a server deems the client to be trusted; for example, after they have logged into a service or if they prove certain characteristics. The redeemed tokens are cryptographically unlinkable to the attestation originally provided by the server, and so they do not reveal anything about the client.

To use Privacy Pass, clients can install an open-source browser extension available in Chrome & Firefox. There have been over 150,000 individual downloads of Privacy Pass worldwide; approximately 130,000 in Chrome and Continue reading

Tales from the Crypt(o team)

Halloween season is upon us. This week we’re sharing a series of blog posts about work being done at Cloudflare involving cryptography, one of the spookiest technologies around. So bookmark this page and come back every day for tricks, treats, and deep technical content.

A long-term mission

Cryptography is one of the most powerful technological tools we have, and Cloudflare has been at the forefront of using cryptography to help build a better Internet. Of course, we haven’t been alone on this journey. Making meaningful changes to the way the Internet works requires time, effort, experimentation, momentum, and willing partners. Cloudflare has been involved with several multi-year efforts to leverage cryptography to help make the Internet better.

Here are some highlights to expect this week:

• We’re renewing Cloudflare’s commitment to privacy-enhancing technologies by sharing some of the recent work being done on Privacy Pass
• We’re helping forge a path to a quantum-safe Internet by sharing some of the results of the Post-quantum Cryptography experiment
• We’re sharing the rust-based software we use to power time.cloudflare.com
• We’re doing a deep dive into the technical details of Encrypted DNS
• We’re announcing support for a new technique we developed with industry partners Continue reading

Cisco Networking Trends Report: ‘Intent-Based Networking Is Coming’

Slow Service Provider Sales Muddle Juniper’s Q3 Earnings

The End of SD-WAN’s Party In China

As I was listening to Network Break Episode 257 from my friends at Packet Pushers, I heard Greg and Drew talking about a new development in China that could be the end of SD-WAN’s big influence there.

China has a new policy in place, according to Axios, that enforces a stricter cybersecurity stance for companies. Companies doing business in China or with offices in China must now allow Chinese officials to get into their networks to check for security issues as well as verifying the supply chain for network security.

In essence, this is saying that Chinese officials can have access to your networks at any time to check for security threats. But the subtext is a little less clear. Do they get to control the CPE as well? What about security constructs like VPNs? This article seems to indicate that as of January 1, 2020, there will be no intra-company VPNs authorized by any companies in China, whether Chinese or foreign businesses in China.

Tunnel Collapse

I talked with a company doing some SD-WAN rollouts globally in China all the way back in 2018. One of the things that was brought up in that interview was that Continue reading

Weekly Wrap: Ex-Cisco Execs Launch Pensando, Target Amazon

Public keys are not enough for SSH security

If your organization uses SSH public keys, it’s entirely possible you have already mislaid one. There is a file sitting in a backup or on a former employee’s computer which grants the holder access to your infrastructure. If you share SSH keys between employees it’s likely only a few keys are enough to give an attacker access to your entire system. If you don’t share them, it’s likely your team has generated so many keys you long lost track of at least one.

If an attacker can breach a single one of your client devices it’s likely there is a known_hosts file which lists every target which can be trivially reached with the keys the machine already contains. If someone is able to compromise a team member’s laptop, they could use keys on the device that lack password protection to reach sensitive destinations.

Should that happen, how would you respond and revoke the lost SSH key? Do you have an accounting of the keys which have been generated? Do you rotate SSH keys? How do you manage that across an entire organization so consumed with serving customers that security has to be effortless to be adopted?

Cloudflare Access launched support Continue reading

Enable GitOps for Kubernetes Security – Part 1

“How do I enable GitOps for my network policies?”

That is a common question we hear from security teams. Getting started with Kubernetes is relatively simple, but moving production workloads to Kubernetes requires alignment from all stakeholders – developers, platform engineering, network engineering, security.

Most security teams already have a high-level security blueprint for their data centers. The challenge is in implementing that in the context of a Kubernetes cluster and workload security. Network policy is a key element of Kubernetes security. Network policy is expressed as an YAML configuration, and works very well with GitOps.

We will do a 3 part blog series covering GitOps for network policies. In part 1 (this part), we cover the overview and getting started with a working example tutorial. In part 2, we will extend the tutorial to cover an enterprise-wide decentralized security architecture. In the final part, we will delve into policy assurance with examples. Note that all policies in Tigera Secure (network policy, RBAC, Threat detection, Logging configuration, etc.) are enforced as YAML configuration files, and can be enforced via a GitOps practice.

By adopting GitOps, security teams benefit as follows.

• Take your policies with you. Kubernetes cluster creation Continue reading