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WordPress Profiling with XHProf (Debugging & Optimizing Speed)
Crowdfunding on Crowd Supply (Review of my experience)
Trusted Boot (Anti-Evil-Maid, Heads, and PureBoot)
WordPress Multisite on the Darknet (Mercator .onion alias)
Nightmare on Lemmy Street (A Fediverse GDPR Horror Story)
Detecting (Malicious) Unicode in GitHub PRs
Continuous Documentation: Hosting Read the Docs on GitHub Pages (2/2)
Hardening Guide for phpList
Introducing BusKill: A Kill Cord for your Laptop
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Ephemeral Firefox as a Site-Specific Browser (3/3)

Site-Specific Ephemeral Firefox featured image showing a firewall between the facebook and firefox icons

This article is a part 3/3 of a series describing how to setup an Ephemeral Firefox session as a Site-Specific Browser. The ultimate goal is to be able to have a self-destructing browsing session that can only access a single company’s services, such as Google or Facebook.

Part 1/3: Ephemeral Firefox in Ubuntu Part 2/3: Ephemeral Firefox with Extensions Part 3/3: Ephemeral Firefox as a Site-Specific Browser

After setting up the Site-Specific Ephemeral Firefox Browser, you can then blacklist services designated to your Site-Specific browser(s) (such as Google or Facebook) from your main browser. This significantly improves your ability to browse the internet without your activity being tracked by these companies — leaving your sensitive data vulnerable to being stolen by hackers.

Michael Altfield

Hi, I’m Michael Altfield. I write articles about opsec, privacy, and devops ➡

About Michael


. . . → Read More: Ephemeral Firefox as a Site-Specific Browser (3/3)

Detect outgoing port blocking with nmap and portquiz.net

This post will describe how to detect if your network is blocking outgoing ports. In this test, we’ll be using nmap and the fine website portquiz.net

Michael Altfield

Hi, I’m Michael Altfield. I write articles about opsec, privacy, and devops ➡

About Michael


. . . → Read More: Detect outgoing port blocking with nmap and portquiz.net

Bypassing Check Point firewall DPI Tor-blocking

This article will describe how to bypass censorship from within any network that uses firewalls using Deep Packet Inspection (DPI) built by the Israeli software company Check Point Software Technologies Ltd, such as is being used by the Miami-Dade’s Public Library System to censor on their public wifi.

I’ve been very fortunate to live in a country where freedom of speech is a well-protected human right and censorship is generally unaccepted. But, I’ve long been aware that many States prefer to assert their control over their citizens by controlling their available information. One of the shining achievements from the Tor Project is a system that allows these unfortunate souls to be able to bypass these censors and access the unfettered Internet. Indeed, the UN affirmed that a State’s attempt to prevent or disrupt dissemination of information online is a violation of international human rights law, as defined by article 19 of the Universal Declaration of Human Rights.

Of course, many States today continue to ban access to the Tor network. In response, Tor provided hidden entry-points called bridge relays that are harder to block. In response to Tor bridges, States purchased firewalls from companies like Check Point to analyze the
. . . → Read More: Bypassing Check Point firewall DPI Tor-blocking

HPKP Best Practices for Let’s Encrypt

This post describes how to generate a few backup public key hashes to add to your HTTP Public Key Pinning (HPKP) config that might save you from bricking your domain if Let’s Encrypt ever gets untrusted like StartCom did.

If you have a healthy distrust of the X.509 PKI trust model, then you’ve probably heard of HPKP (and probably also HSTS & CAA). Website certificate pinning was a trend first started by google, who hard-coded a pin of their certificates in their Chrome browser. Eventually, google helped build a more standardized pinning method under RFC 7469. And today, it’s supported by Chrome, Firefox, and Opera.

Pinning is a great TOFU improvement to https, but–if misconfigured–you could “brick” your domain–making it so that your client’s browsers will refuse to let them access your site for months or years (interestingly, this has also caused some security experts to think of how HPKP could be abused in ransom-ware). Therefore, it’s a good idea to follow a few HPKP Best Practices.

Michael Altfield

Hi, I’m Michael Altfield. I write articles about opsec, privacy, and devops ➡

About Michael


. . . → Read More: HPKP Best Practices for Let’s Encrypt

Howto Guide: Whole House VPN with Ubiquiti + Cryptostorm (netflix safe!)

This post will describe what hardware to buy & how to configure it so that you have 2 wireless networks in your house: One that seamlessly forces all of the traffic on that network through a VPN–and one that connects to the Internet normally . When finished, the internet activity for any device connected to the first network will be entirely encrypted so that the ISP cannot see which websites are visited*, what software you use, and what information you send & receive on the internet.

* Assuming your config doesn’t leak DNS; see improvements section

Update 2017-08-25: Added “kill switch” firewall rule that prevents LAN traffic from escaping to the ISP unless it passed through the VPN’s vtun0 interface first. Following this change, if the VPN connection is down, the internet will not be accessible (as desired) over the ‘home’ wifi network (without this, the router bypasses the VPN by sending the packets straight to the ISP–giving a false sense of privacy).

Update 2021-02-01: Fixed GitHub URL of cryptostorm’s free OpenVPN configuration file Update 2021-02-14: Fixed GitHub URL of cryptostorm’s paid OpenVPN configuration file

Update: I wrote this guide in 2017. It’s intended for an audience that has
. . . → Read More: Howto Guide: Whole House VPN with Ubiquiti + Cryptostorm (netflix safe!)

Let’s Encrypt!

Finally, this website is (only) accessible over https!

Michael Altfield

Hi, I’m Michael Altfield. I write articles about opsec, privacy, and devops ➡

About Michael

tech.michaelaltfield.net/

UCF Wifi in Ubuntu

This month (September 2011), UCF officially killed the “UCF” SSID to be replaced by “UCF_WPA” and “UCF_WPA2.” Configuring Ubuntu Linux to connect to the UCF WPA2 network is neither trivial nor documented by UCF.

To aid other UCF Ubuntu users, I created a Wireless article on the unofficial UCF wiki. This includes links to the official UCF certificates and instructions on how to connect to the UCF_WPA2 network in Ubuntu.

Michael Altfield

Hi, I’m Michael Altfield. I write articles about opsec, privacy, and devops ➡

About Michael

tech.michaelaltfield.net/

UCF Wifi Rant

While I frustratingly waited to connect to the UCF Wifi after a recent change to their system, I typed up the following email complaint to the UCF DoIT Manager. If *you* have also had issues with unstable/dropped connections, slow bandwidth, latency, or the inability to connect to the UCF Wifi, I urge you to also contact the UCF Department of Information Technology via:

cst@ucf.edu = General bob.yanckello@ucf.edu = Bob Yanckello (UCF Chief Technology Officer) lou.garcia@ucf.edu = Lou Garcia (UCF Network Manager [responsible for wireless services]) chrisv@mail.ucf.edu = Chris Vakhordjian (Information Security Office) tim.larson@ucf.edu = Tim Larson (ERP Consultant) jim.ennis@ucf.edu = Jim Ennis (Enterprise Systems & Operations) andy.hulsey@ucf.edu = Andy Hulsey (Telecommunications [includes Network Services]) aaron.streimish@ucf.edu = Aaron Streimish (Project Performance & Management Office)

Email below

While I understand the benefit of encrypted wireless communications, UCF’s decision to require all student wireless clients to use WPA without preparing to sufficiently upgrade the wireless infrastructure has rendered the UCF Wifi *unusable*.

Allow me to provide a brief log of my Internet Experience this afternoon (2011-09-15).

12:02 – attempt to connect to WiFi – fail for 9 minutes 12:11 – connected 12:11 – google ’email ucf department of information technology’ 12:12 – disconnected
. . . → Read More: UCF Wifi Rant

Iterative MITM Packet Sniffer

So, I got into a discussion with a friend of mine in my Computer Security class at UCF about this script. I’m posting this for historical and educational purposes only. As always, I never condone the implementation of any of my content for malicious intent. Moreover, this script has flaws that * would make it useless in such a scenario. Don’t do it!

Here’s a script I hacked up last semester when I was playing with MITM attacks and packet eavesdropping with ettercap:. This scripts will automatically:

fake its MAC Address get a new IP Address collect a list of hosts on the same subnet as itself iterate through and ARP poison: each of these hosts one at a time for 5 minutes each save all data collected in host-specific files in a timestamped directory repeat until the hard drive is full Michael Altfield

Hi, I’m Michael Altfield. I write articles about opsec, privacy, and devops ➡

About Michael


. . . → Read More: Iterative MITM Packet Sniffer

Clone Xen RHEL5 (CentOS 5.2) VM

Hello world! I just updated my whole server environment and, my, things are looking good. Anyway, I had to run through these steps a half dozen times, so I thought I would post it here for myself and (maybe even) others.

Here’s the commands I ran to turn a clone of my base RHEL5 (CentOS 5.2) Xen image into another working virtual machine on my RHEL5 (CentoOS 5.2) Xen Host:

Michael Altfield

Hi, I’m Michael Altfield. I write articles about opsec, privacy, and devops ➡

About Michael

tech.michaelaltfield.net/