There are many types of multi factor authentication (MFA) tokens available. Some are virtual, some are software (apps), and some are hardware. Each has their benefits and their disadvantages. This paper discusses some of the concerns with each type of authentication token type and what is recommended for secure networks …
Other articles
Signal routing
DMARC Works
Earlier today I received a few notifications of bounced mail from Google. This was odd seeing as how I hadn’t sent any mail to Google in a while. Upon further inspection, the messages originated from an application running on one of my servers. These were password reset messages destined …
E-mail Security
Way back when, e-mail was from server-to-server, and really client-to-server as well, without much thought to security. Messages were transmitted in plain text (no encryption) and the only people reading your mail (literally) were the system administrators who ran the email server. Of course, those system administrators knew what was …
Updating e-mail security features on my server.
I recently learned of a new security process called SMTP MTA Strict Transport Security, or MTA-STS for short. It’s not new, exactly, but it hasn’t been talked about a lot, either. Basically, it does what HTTP Strict Transport Security, HSTS, does for websites and informs the connecting client …
Security of Shredding Services
When I started dealing with serious information security we created a lot of paper. This wasn’t regular information printed on paper but very sensitive information that could be very damaging if it ever found its way out of the building. If this paper was ever deemed to be trash …
A review of ProtonMail
Update (2018-07-25)
Shortly after publishing this original post, many of my concerns were addressed. ProtonMail now supports sending mail that is signed and/or encrypted using OpenPGP. This is a huge benefit to the secure-email community. It is also possible to use your own key which allows me to use …
Ditch All Those Other Messaging Apps: Here's Why You Should Use Signal
Content Security Policy and WordPress
For your protection, I've been working on securing this website with all the proper security HTTP headers. Of course, by running WordPress as the backend, I'm making it easy to manage all the data but making it difficult to manage all the pieces and parts of the system's backend. The …
read moreSecuring email to Gmail
I've been working on securing my postfix configuration to enforce certificate validation and encryption on some known, higher-volume, or more sensitive connections between SMTP servers (port 25).
On many of the connections I've setup for secure transport there have been no problems (assuming proper TLS certificates are used). Unfortunately Gmail …
read moreRFC: Using video conferencing for GPG key signing events
A thought that I haven't had a chance to fully consider (so I'm asking the Internet to do that for me)...
I have a geographically-diverse team that uses GPG to provide integrity of their messages. Usually, a team like this would all huddle together and do a formal key-signing event …
read moreEncryption you don't control is not a security feature
Catching up on my blog reading, this morning, led me to an article discussing Apple's iMessage program and, specifically, the encryption it uses and how it's implemented. Go ahead and read the article; I'll wait.
The TL;DR of that article is this: encryption you don't control is not a …
read morePostfix Encryption
How to really screw up TLS
I've noticed a few of my favorite websites failing with some odd error from Firefox.
The Firefox error message is a bit misleading. It actually has nothing to do with the website supporting SSL 3.0 but the advanced info is spot on. The error "ssl_error_no_cypher_overlap" means that the client …
read moreAbility to remove TLS 1.0 from httpd in CentOS 6
Due to a bug in mod_ssl, the ability to remove TLS 1.0 (and only support TLS 1.1 and/or TLS 1.2) has not been available. The fix has now made it to CentOS 6 and you can now fine-tune your cryptographic protocols with ease.
Before the fix …
read moreOkay, this is a neat attack...
This morning I received an email from my "administrator" saying that I needed to validate my email address within the next 48 hours or my email account would be suspended. Seeing as how I'm my own email administrator, I couldn't remember sending out such a message, I decided that this …
read moreSigning PGP keys
If you've recently completed a key signing party or have otherwise met up with other people and have exchanged key fingerprints and verified IDs, it's now time to sign the keys you trust. There are several different ways of completing this task and I'll discuss two of them now.
caff …
PGP Keysigning Event and CACert Assertion at SELF2014
SouthEast LinuxFest is happening this upcoming weekend. I offered to host a PGP (I'll substitute PGP for GPG, GnuPG, and other iterations) keysigning and CACert Assertion event and have been scheduled for 6:30 PM in the Red Hat Ballroom. Since there is a little bit of planning needed on …
read moreGenerating a PGP key using GnuPG
Generating a PGP using GnuPG (GPG) is quite simple. The following shows my recommendations for generating a PGP key today.
$ gpg --gen-key gpg (GnuPG) 1.4.16; Copyright (C) 2013 Free Software Foundation, Inc. This is free software: you are free to change and redistribute it. There is NO WARRANTY …
read moreSecure E-mail
E-mail is inherently insecure. Just as sending a post card, any message sent by e-mail can be read by any number of people, including those monitoring the network path, the servers that process the message along its route, or anyone with access to the distant computer. Basically you should consider …
read moreSSL/TLS Trends
My friend Hubert has started compiling statistics of Alexa's top 1 million websites. Specifically, he's looking at their SSL/TLS settings and attempting to show trends in the world that is port 443. He recently released his May numbers showing a slow but mostly improving security environment. I'm hoping he'll …
read moreSTARTTLS for SMTP
Okay, I don't really mean to advocate this as a privacy solution because it is and it isn't. If you truly want privacy of your email you mustuse end-to-end encryption like PGP/GnuPG or S/MIME. That said, I think it's good to encrypt things, even ciphertext, over the …
read more256 Bits of Security
This is an incomplete discussion of SSL/TLS authentication and encryption. This post only goes into RSA and does not discuss DHE, PFS, elliptical, or other mechanisms.
In a previous post I created an 15,360-bit RSA key and timed how long it took to create the key. Some may …
read moreTime to generate a 15,360-bit RSA key
$ time openssl genrsa 15360Generating RSA private key, 15360 bit long modulus<magic happens>
real 2m39.541suser 2m39.236ssys 0m0.006sKicking RC4 out the door
I've been arguing with my web hosting company about their use of RC4. Like many enterprise networks they aren't consistent across all their servers with respect to available ciphers and such. It appears that all customer servers support TLS_RSA_WITH_CAMELLIA_256_CBC_SHA and TLS_RSA_WITH_CAMELLIA_128_CBC_SHA, in addition to TLS_RSA_WITH_RC4_128_SHA (although the latter is preferred …
read moreHow secure are those SSL and SSH keys anyway?
Thought I'd pass along this research study, The keys to the kingdom, as I found it to be quite interesting (especially when you scan the entire Internet for your data). If you don't understand the math explanation at the beginning just continue reading as you don't need to have a …
read moreWhy Android SSL was downgraded from AES256-SHA to RC4-MD5 in late 2010
Just ran across this article discussing how horrible the cipher preference list is in Android. That's a lot of bad crypto on the streets right now.
Why Android SSL was downgraded from AES256-SHA to RC4-MD5 in late 2010
read moreTrusting Trusted CAs
Like it or not, the basis of trust for much of the Internet is based on Certificate Authorities (CA). Companies like Verisign, GoDaddy, and GeoTrust are in the trust business. They will sell you cryptographic proof of your Internet assets (namely your domain name) that others can use to verify …
read moreSFGate: If You Send To Gmail, You Have 'No Legitimate Expectation Of Privacy'
SFGate: If You Send To Gmail, You Have 'No Legitimate Expectation Of Privacy'
Not that this is really news but if you hand your message to a third-party for delivery you have no expectation of privacy. Agree with it or not that's the way it is inside the United States …
read moreTor and HTTPS
An excellent description of how Tor and HTTPS can help protect your online privacy and secure your web communications.
read moreLawmakers of both parties voice doubts about NSA surveillance programs
Lawmakers of both parties voice doubts about NSA surveillance programs
I'm happy to read the Washington Post story discussing the House committee's hearing on the NSA's domestic spying programs. It's encouraging that both parties aren't happy with the programs and that "...there are not enough votes in the House now …
read morePrivacy articles to read
Why Privacy Matters Even if You Have 'Nothing to Hide' by The Chronicle Review
Using Metadata to Find Paul Revere by Kieran Healy
We Should All Have Something To Hide by Moxie Marlinspike
read moreSecure GnuPG configuration
Someone recently asked what my GPG.conf file looks like since he hadn't updated his in... years. Okay, let's take a look and I'll try to explain what each setting is and why I feel it is important. I'm not guaranteeing this as being complete and I welcome input from …
read moreInadvertant data leakage from GnuPG
I was recently introduced to a privacy issue when refreshing your OpenPGP keys using GnuPG. When refreshing your public key ring using a public key server GnuPG will generally use the OpenPGP HTTP Key Protocol (HKP) to synchronize keys. The problem is that when you do refresh your keys using …
read moreThe Guardian: I'd pay more for tech products with greater privacy from surveillance
The Guardian: I'd pay more for tech products with greater privacy from surveillance
I thought this was a fantastic article. It skims over the fact that if you aren't paying for a service then you are probably the product being sold. Google, Facebook, and many other companies make billions of …
read moreEncrypting SMS messages and phone calls on Android
Much of our daily lives are contained within our smartphones and computers. Email, text messages, and phone calls all contain bits and pieces of information that, in the wrong hands, could harm our privacy. Unfortunately many people either don't understand how vulnerable their data is when sent across the Internet …
read morePort scanning /0 using insecure embedded devices
Someone sent me a link to the Port scanning /0 using insecure embedded devices article that was recently published. Describing the Carna Botnet, this project aimed to prove (or disprove) the hypothesis that there were one hundred thousand open systems on the Internet in which to make a botnet. I …
read morePrivacy Upgrade: Encrypted Internet browsing
Many websites have both the traditional, unencrypted HTTP and the SSL or TLS-encrypted HTTPS addresses available to access their content. Wikipedia is one good example of this functionality. You can easily view Wikipedia using traditional HTTP protocol but if you wanted or needed a little more privacy the HTTPS …
read moreHow PGP actually works...
The dangers of mandatory software on smartphones
Removing dependencies when using yum
A forthcoming article on the Red Hat Security Blog got me to ask the question: is it possible to have yum remove dependencies when uninstalling packages? The answer is a somewhat surprising "yes"! The functionality is turned off by default for a good reason but that's no reason why everyone …
read moreHashing Algorithm: Is your GPG configuration secure?
US-CERT: Java vulnerability
A bad (as in it's a 10) Java vulnerability has been discovered. Affecting Java 7 Update 10 and prior versions, this vulnerability can allow an untrusted Java applet to escalate its privileges without requiring code signing.
Currently, the only defense to this vulnerability is to disable Java in your browser …
read morePassword strength, more characters are better than complexity
In a recent PBS Newshour article discussing the recent Yahoo! password list theft, a reference to a chart showing howshort passwords can still be secure was added to the story. The data and conclusions included in that chart were disturbing to me, to say the least. While complexity does …
read moreNew year, updated keys.
I run a SKS key server and watch my daily numbers to see how many keys get updated, etc. Being a numbers guy I wondered how many people, like me, update their GPG keys, I specifically update the expiration date and generate new encryption keys annually, at the beginning of …
read moreEnd user security for web browsing
Someone asked me, earlier this week, how to setup a "very secure Fedora 16..." system for a user that mostly surfs the web and uses email. Instead of responding directly to that user I'm writing this in order to get others to comment and provide additional information that I may …
read moreComplex, secure passwords made easy
I attended a talk by Aaron Toponce at Ohio Linux Fest on password security. Everyone knows you shouldn't use a simple password that is easily guessable and that you shouldn't use the same password for every account but how do you make unique, complex passwords and only use it once …
read moreDoes Google's multi-factor authentication make your security weaker?
A few months back Google introduced "2-step verification" for all Google accounts. This amounted to multi-factor authentication (something you know (password) and something you have (token)) for all web-based Google applications. Cool, right? They created an app for the Android, I-Phone, and Blackberry devices that acted like a token and …
read moreFOSS solutions could help when communication failures occur.
Not to get into the political battle that is occurring in Egypt but I wonder how the organization of both news gathering agencies and organizers would have fared had they been using StatusNet software (the software that supports identi.ca) on a local computer inside the country instead of utilizing …
read moreProposed encryption "backdoor" for the US Government and how it will fail.
If you haven't heard, the President is drafting legislation that may require hardware and software developers to install backdoors in their encryption solutions and give the keys to these backdoors to the US Government. In my opinion, this is an increadibly bad idea.
- This has already been tried and failed …
HTTPS-Everywhere
The other day I found myself reading about a new Firefox plugin that will automatically select HTTPS for various websites (and you can make your own rules, too). The plugin, created by the EFF, is named HTTPS Everywhere.
Basically it knows that there are several popular websites out there that …
read morePrivacy risk in your email client?
That was a switch in my email client Thunderbird 3 that I did not have checked because I wasn't sure what it was doing and I certainly didn't want my Inbox to be cleared every time I exited the software. So I decided to do a search for it to …Protecting your email from disclosure
read moreClimate talk, Alaska government business, and Dave Briggs. What do these three things have in common? Each of these subjects had more light shown on them by someone cracking email messages and releasing those messages to the public over the Internet. Of course there are many more of these events …
Expiring OpenPGP keys...
A discussion was had on one of the Fedora IRC channels months ago about the "proper" way to handle expiring GPG keys without breaking the web of trust. It was my opinion that by generating new keys every so often (yearly?) that it would increase the security of the overall …
read moreSecuring Instant Messaging
More and more sensitive communications are occurring over unsecure instant messaging (IM) systems. These messages go through a third-party and can be read anywhere along the way. An easy, open-source solution does exist to help protect these communications, however.
First you need the IM client called Pidgin. This client works …
read morePlaintext Recovery Attack Against OpenSSH
https://isc.sans.edu/diary/Plaintext+Recovery+Attack+Against+OpenSSH/5366
SANS Internet Storm Center is reporting an attack against OpenSSH. Please go to the link above for more information as they are posting updates there.
read moreOpen Source down falls when dealing with the US Government
I don't hide the fact that I am a contractor to a few US Government organizations and deal specifically with security issues. As such, I'm asked if I'm seeing any open source or Linux items in my daily work. Unfortunately the answer is always "not as much as I'd like …
read moreSANS ISC goes to YELLOW: SSH vulnerability
SANS Internet Storm Center has raised the Internet Threat Level to YELLOW in response to a report of a SSH vulnerability on all Debian-based systems that generated SSH keys between September 2003 and 13 May 2008.
read moreInternet Backbone Outage Reported in the Middle-East
SANS Internet Storm Center is reporting that possibly several under-sea cables have been cut near the coast of Egypt. Several countries in that area have reported slow connections or complete packet loss. India is experiencing a 50% packet loss at times due to all their traffic having to flow out …
read moreProblems at Radio Station W4OTN
I've been having problems with my radio station lately and it has really started to bother me. I've used two antennas and haven't been satisfied with either one of them. Before I was using a 40-80-160 dipole but the 80m portion was too long and didn't want to work right …
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