iPerf2 vs iPerf3 | Panos Vouzis | WLPC Phoenix 2020 – YouTube
Short video on differences.
Unnumbered Ethernet Interfaces, DHCP Edition
Last week we explored the basics of unnumbered IPv4 Ethernet interfaces, and how you could use them to save IPv4 address space in routed access networks. I also mentioned that you could simplify the head-end router configuration if you’re using DHCP instead of per-host static routes.
Obviously you’d need a smart DHCP server/relay implementation to make this work. Simplistic local DHCP server would allocate an IP address to a client requesting one, send a response and move on. Likewise, a DHCP relay would forward a DHCP request to a remote DHCP server (adding enough information to allow the DHCP server to select the desired DHCP pool) and forward its response to the client.
Unnumbered Ethernet Interfaces, DHCP Edition
Last week we explored the basics of unnumbered IPv4 Ethernet interfaces, and how you could use them to save IPv4 address space in routed access networks. I also mentioned that you could simplify the head-end router configuration if you’re using DHCP instead of per-host static routes.
Obviously you’d need a smart DHCP server/relay implementation to make this work. Simplistic local DHCP server would allocate an IP address to a client requesting one, send a response and move on. Likewise, a DHCP relay would forward a DHCP request to a remote DHCP server (adding enough information to allow the DHCP server to select the desired DHCP pool) and forward its response to the client.
CVE-2021-31440: Kubernetes container escape using eBPF
In a recent post by ZDI, researchers found an out-of-bounds access flaw (CVE-2021-31440) in the Linux kernel’s (5.11.15) implementation of the eBPF code verifier: an incorrect register bounds calculation occurs while checking unsigned 32-bit instructions in an eBPF program. The flaw can be leveraged to escalate privileges and execute arbitrary code in the context of the kernel.
This vulnerability allows a local privilege escalation, which means an attacker with non-root access to the system can gain higher privileges by exploiting this vulnerability. The non-root access can be a user account without sudo or group privileges, which are usually provided to the application user.
Why you should be worried
In a Kubernetes environment, containers use the host kernel to run themselves. Therefore, the execution of malicious eBPF code as an unprivileged user in the context of the kernel can result in container escape and privilege escalation to the host.
Unprivileged users inside the container need CAP_SYS_ADMIN permission already assigned to the container to run a malicious eBPF program. For Linux kernels 5.8 and above, a new permission, CAP_BPF, is added to allow users to run eBPF programs. CAP_BPF is a subset of CAP_SYS_ADMIN.
In Kubernetes, Continue reading
The Hedge 87: Jordan Holand and nPrint
The network monitoring world is rife with formats for packets being measured—every tool has its own format. What would make things a lot better for network engineers is a standard data representation for packet analysis, no matter what format packets are captured in. Jordan Holland joins Russ White and Tom Ammon on this episode of the Hedge to discuss the problem and nprint, a standard packet analysis format and tools for converting from other formats.
CVE-2021-31440: Kubernetes container escape using eBPF
In a recent post by ZDI, researchers found an out-of-bounds access flaw (CVE-2021-31440) in the Linux kernel’s (5.11.15) implementation of the eBPF code verifier: an incorrect register bounds calculation occurs while checking unsigned 32-bit instructions in an eBPF program. The flaw can be leveraged to escalate privileges and execute arbitrary code in the context of the kernel.
This vulnerability allows a local privilege escalation, which means an attacker with non-root access to the system can gain higher privileges by exploiting this vulnerability. The non-root access can be a user account without sudo or group privileges, which are usually provided to the application user.
Why you should be worried
In a Kubernetes environment, containers use the host kernel to run themselves. Therefore, the execution of malicious eBPF code as an unprivileged user in the context of the kernel can result in container escape and privilege escalation to the host.
Unprivileged users inside the container need CAP_SYS_ADMIN permission already assigned to the container to run a malicious eBPF program. For Linux kernels 5.8 and above, a new permission, CAP_BPF, is added to allow users to run eBPF programs. CAP_BPF is a subset of CAP_SYS_ADMIN.
In Kubernetes, Continue reading
Exploring VMware’s Kubernetes App Connectivity and Security Solution: A Deep Dive, with Demos
Modern apps need to run in multi-cluster, multi-cloud environments across a mix of traditional and microservices architectures. In this context, enterprise platform, infrastructure, and operations teams are presented with unique challenges in securely connecting and managing modern workloads, in delivering scalable services, or bridging between traditional VM workloads and containers, and supporting production operations for modern apps.
VMware recently introduced the “VMware Modern Apps Connectivity solution”, which brings together the advanced capabilities of Tanzu Service Mesh (TSM) and VMware NSX Advanced Load Balancer ALB (formerly Avi Networks) address today’s unique enterprise challenges.
In this blog, we’ll take a deeper look at this solution and demonstrate how its cloud-native principles enable a set of important use cases that automate the process of connecting, observing, scaling, and better securing applications across multi-site environments and clouds. We’ll also show how state-of-the-art capabilities in this solution — like Global Server Load Balancing (GSLB) and Intelligent Autoscaling — enable enterprises to deliver advanced use cases such as cloud-bursting.
Step 0: Set up (typical HA architecture for a modern distributed app)
Let’s start by looking at our set-up, which is a typical architecture for a highly-available modern app deployment Continue reading
Confronting European Encroachment on Encryption
In late 2020, as Portugal prepared to take over the rotating Presidency of the Council of the European Union (EU), the Internet Society’s Portugal Chapter began ramping up its advocacy against worrying new plans to create encryption backdoors. The Council of the European Union, in a resolution in November 2020, and the European Commission (EC), in a […]
The post Confronting European Encroachment on Encryption appeared first on Internet Society.
Day Two Cloud 101: Closing The Network/Cloud Gap Before You Fall In (Sponsored)
On today's episode, sponsored by BlueCat Networks, we examine the technology and human challenges that arise when you integrate on-prem and the public cloud. You can't continue to do things in the cloud with traditional toolsets and processes. You need to update the tech and the people, including how they collaborate. We also discuss a new report that examines the need for, and challenges of, integrating networking and cloud teams. Our guest is Andrew Wertkin, Chief Strategy Officer at BlueCat.
The post Day Two Cloud 101: Closing The Network/Cloud Gap Before You Fall In (Sponsored) appeared first on Packet Pushers.
Day Two Cloud 101: Closing The Network/Cloud Gap Before You Fall In (Sponsored)
On today's episode, sponsored by BlueCat Networks, we examine the technology and human challenges that arise when you integrate on-prem and the public cloud. You can't continue to do things in the cloud with traditional toolsets and processes. You need to update the tech and the people, including how they collaborate. We also discuss a new report that examines the need for, and challenges of, integrating networking and cloud teams. Our guest is Andrew Wertkin, Chief Strategy Officer at BlueCat.Smart Security Strategies for the World of Social Media
As a way to avoid risks, social media security is vital for every business or enterprise in blocking targeted attacks, securing corporate accounts from compromise, fighting scams, and frauds.Celebrating 7 Years of Project Galileo
Every June, we celebrate the anniversary of Project Galileo. This year, we are proud to celebrate seven years of protecting the most vulnerable groups on the Internet from cyber attacks. June is a busy month for us at Cloudflare, with the anniversary of Project Galileo and Access Now’s RightsCon, one of the largest events on human rights in the digital age. As we collaborate with civil society on topics from technology, privacy, digital security and public policy, we learn how to better protect critical voices on the Internet but also how to use the Cloudflare network to make positive changes to the Internet ecosystem.
We started Project Galileo in 2014 with the idea that we need to protect voices that are targeted for working in sensitive areas. As such, we give these voices the resources to protect themselves online against powerful opponents. Whether their opponent’s aim is to intimidate, silence, or steal sensitive information, cyber attacks can cause significant damage to organizations that work in areas such as human rights, independent media, education, and social justice. As the world moves online — a factor accelerated by COVID-19 — access to powerful cybersecurity tools is critical for organizations around the world. Continue reading
Real-Life Network-as-a-Graph Examples
After reading the Everything Is a Graph blog post, Vadim Semenov sent me a long list of real-life examples (slightly edited):
I work in a big enterprise and in order to understand a real packet path across multiple offices via routers and firewalls (when mtr or traceroute don’t work – they do not show firewalls), I made OSPF network visualization based on LSDB output. The idea is quite simple – save information about LSA1 and LSA2 (LSA5 optionally) and that will be enough in order to build a graph (use show ip ospf database router/network on Cisco devices).
Real-Life Network-as-a-Graph Examples
After reading the Everything Is a Graph blog post, Vadim Semenov sent me a long list of real-life examples (slightly edited):
I work in a big enterprise and in order to understand a real packet path across multiple offices via routers and firewalls (when mtr or traceroute don’t work – they do not show firewalls), I made OSPF network visualization based on LSDB output. The idea is quite simple – save information about LSA1 and LSA2 (LSA5 optionally) and that will be enough in order to build a graph (use show ip ospf database router/network on Cisco devices).