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My GPG key has lasted me well, over 18 years, but it's a v2 key and therefore no longer supported by newer versions of GnuPG. So it's time to move to a new one. I've made a transition statement available. If you signed my old key please consider signing the new one.

Here is a quick writeup of the protocol for the iKettle taken from my Google+ post earlier this month. This protocol allows you to write your own software to control your iKettle or get notifications from it, so you can integrate it into your desktop or existing home automation system.

The iKettle is advertised as the first wifi kettle, available in UK since February 2014. I bought mine on pre-order back in October 2013. When you first turn on the kettle it acts as a wifi hotspot and they supply an app for Android and iPhone that reconfigures the kettle to then connect to your local wifi hotspot instead. The app then communicates with the kettle on your local network enabling you to turn it on, set some temperature options, and get notification when it has boiled.

Once connected to your local network the device responds to ping requests and listens on two tcp ports, 23 and 2000. The wifi connectivity is enabled by a third party serial to wifi interface board and it responds similar to a HLK-WIFI-M03. Port 23 is used to configure the wifi board itself (to tell it what network to connect to and so on). Port 2000 is passed through to the processor in the iKettle to handle the main interface to the kettle.

Port 2000, main kettle interface

The iKettle wifi interface listens on tcp port 2000; all devices that connect to port 2000 share the same interface and therefore receive the same messages. The specification for the wifi serial board state that the device can only handle a few connections to this port at a time. The iKettle app also uses this port to do the initial discovery of the kettle on your network.


Sending the string "HELLOKETTLE\n" to port 2000 will return with "HELLOAPP\n". You can use this to check you are talking to a kettle (and if the kettle has moved addresses due to dhcp you could scan the entire local network looking for devices that respond in this way. You might receive other HELLOAPP commands at later points as other apps on the network connect to the kettle.

Initial Status

Once connected you need to figure out if the kettle is currently doing anything as you will have missed any previous status messages. To do this you send the string "get sys status\n". The kettle will respond with the string "sys status key=\n" or "sys status key=X\n" where X is a single character. bitfields in character X tell you what buttons are currently active:

Bit 6Bit 5Bit 4Bit 3Bit 2Bit 1

So, for example if you receive "sys status key=!" then buttons "100C" and "On" are currently active (and the kettle is therefore turned on and heating up to 100C).

Status messages

As the state of the kettle changes, either by someone pushing the physical button on the unit, using an app, or sending the command directly you will get async status messages. Note that although the status messages start with "0x" they are not really hex. Here are all the messages you could see:

sys status 0x100100C selected
sys status 0x9595C selected
sys status 0x8080C selected
sys status 0x10065C selected
sys status 0x11Warm selected
sys status 0x10Warm has ended
sys status 0x5Turned on
sys status 0x0Turned off
sys status 0x8005Warm length is 5 minutes
sys status 0x8010Warm length is 10 minutes
sys status 0x8020Warm length is 20 minutes
sys status 0x3Reached temperature
sys status 0x2Problem (boiled dry?)
sys status 0x1Kettle was removed (whilst on)

You can receive multiple status messages given one action, for example if you turn the kettle on you should get a "sys status 0x5" and a "sys status 0x100" showing the "on" and "100C" buttons are selected. When the kettle boils and turns off you'd get a "sys status 0x3" to notify you it boiled, followed by a "sys status 0x0" to indicate all the buttons are now off.

Sending an action

To send an action to the kettle you send one or more action messages corresponding to the physical keys on the unit. After sending an action you'll get status messages to confirm them.

set sys output 0x80Select 100C button
set sys output 0x2Select 95C button
set sys output 0x4000Select 80C button
set sys output 0x200Select 65C button
set sys output 0x8Select Warm button
set sys output 0x8005Warm option is 5 mins
set sys output 0x8010Warm option is 10 mins
set sys output 0x8020Warm option is 20 mins
set sys output 0x4Select On button
set sys output 0x0Turn off

Port 23, wifi interface

The user manual for this document is available online, so no need to repeat the document here. The iKettle uses the device with the default password of "000000" and disables the web interface.

If you're interested in looking at the web interface you can enable it by connecting to port 23 using telnet or nc, entering the password, then issuing the commands "AT+WEBS=1\n" then "AT+PMTF\n" then "AT+Z\n" and then you can open up a webserver on port 80 of the kettle and change or review the settings. I would not recommend you mess around with this interface, you could easily break the iKettle in a way that you can't easily fix. The interface gives you the option of uploading new firmware, but if you do this you could get into a state where the kettle processor can't correctly configure the interface and you're left with a broken kettle. Also the firmware is just for the wifi serial interface, not for the kettle control (the port 2000 stuff above), so there probably isn't much point.

Missing functions

The kettle processor knows the temperature but it doesn't expose that in any status message. I did try brute forcing the port 2000 interface using combinations of words in the dictionary, but I found no hidden features (and the folks behind the kettle confirmed there is no temperature read out). This is a shame since you could combine the temperature reading with time and figure out how full the kettle is whilst it is heating up. Hopefully they'll address this in a future revision.

Security Implications

The iKettle is designed to be contacted only through the local network - you don't want to be port forwarding to it through your firewall for example because the wifi serial interface is easily crashed by too many connections or bad packets. If you have access to a local network on which there is an iKettle you can certainly cause mischief by boiling the kettle, resetting it to factory settings, and probably even bricking it forever. However the cleverly designed segmentation between the kettle control and wifi interface means it's pretty unlikely you can do something more serious like overiding safety (i.e. keeping the kettle element on until something physically breaks).

"Before" and "After" video:

We were looking for a cheap laser lighting effect for our weekend parties and saw one that looked impressive, the Lanta Quasar Buster 2, and for only £30 new. The unit has both a red and green laser and and a nice moving effect that looks like the beams splits up and recombine again. It promised "sound activation" and we thought that meant it would do some clever sound to light effect, but it really does mean sound activation and just turns itself on when it hears a sound, then off again when it's silent. So out of the box the laser has three modes; the first lets you just set the speed of the effect with the lasers constantly on, the second strobes the lasers on and off to a speed you can set, and the third is the usless sound activation mode.


Warrany void if removed. I didn't technically "remove" the sticker though.


Opening the unit showed that it was easily hackable; all the connections to the control panel were via connectors. One connector provides +5v to the cooling fan, another +5v to a separate board that handles powering the two lasers, another connects to the motor the turns the optics to produce the burst effect, and the final one has a logic level signal to tell the laser power board if the lasers should be on or off.

Since the laser power board is completely separate we can just replace this control panel with one of our own and then we can control the laser on/off and the speed of the motor (actually we could control the direction too but it doesn't really make the effect look any better so I leave it as one direction). And we can always swap the original board back in the future.

My new control board comprises of an Arduino pro mini compatible board, a rotary encoder for setting the mode and levels, a mic with simple opamp preamp, and a MSGEQ7 chip to do all the hard work of analysing the levels of various frequencies. The optics motor is now simply driven using a PWM output via a MOSFET I had spare.



Rough source and circuit diagram are available from github; some components don't have values if it doesn't really matter and others (like the MOSFET) can be changed as I just used things I happened to have in my component boxes. I'm still playing with different effects in software to see what works best.

You can read my Enterprise Linux 6.3 to 6.4 risk report on the Red Hat Security Blog.

"for all packages, from release of 6.3 up to and including 6.4, we shipped 108 advisories to address 311 vulnerabilities. 18 advisories were rated critical, 28 were important, and the remaining 62 were moderate and low."

"Updates to correct 77 of the 78 critical vulnerabilities were available via Red Hat Network either the same day or the next calendar day after the issues were public. The other one was in OpenJDK 1.60 where the update took 4 calendar days (over a weekend)."

And if you are interested in how the figures were calculated, here is the working out:

Note that we can't just use a date range because we've pushed some RHSA the weeks before 6.4 that were not included in the 6.4 spin. These issues will get included when we do the 6.4 to 6.5 report (as anyone installing 6.4 will have got them when they first updated).

So just after 6.4 before anything else was pushed that day:

** Product: Red Hat Enterprise Linux 6 server (all packages)
** Dates: 20101110 - 20130221 (835 days)
** 397 advisories (C=55 I=109 L=47 M=186 )
** 1151 vulnerabilities (C=198 I=185 L=279 M=489 )

** Product: Red Hat Enterprise Linux 6 Server (default installation packages)
** Dates: 20101110 - 20130221 (835 days)
** 177 advisories (C=11 I=71 L=19 M=76 )
** 579 vulnerabilities (C=35 I=133 L=159 M=252 )

And we need to exclude errata released before 2013-02-21 but not in 6.4:

RHSA-2013:0273 [critical, default]
RHSA-2013:0275 [important, not default]
RHSA-2013:0272 [critical, not default]
RHSA-2013:0271 [critical, not default]
RHSA-2013:0270 [moderate, not default]
RHSA-2013:0269 [moderate, not default]
RHSA-2013:0250 [moderate, default]
RHSA-2013:0247 [important, not default]
RHSA-2013:0245 [critical, default]
RHSA-2013:0219 [moderate, default]
RHSA-2013:0216 [important, default]

Default vulns from above: critical:12 important:2 moderate:16 low:3
Non-Default vulns from above: critical:4 important:2 moderate:5 low:0

This gives us "Fixed between GA and 6.4 iso":

** Product: Red Hat Enterprise Linux 6 server (all packages)
** Dates: 20101110 - 20130221 (835 days)
** 386 advisories (C=51 I=106 L=47 M=182 )
** 1107 vulnerabilities (C=182 I=181 L=276 M=468 )

** Product: Red Hat Enterprise Linux 6 Server (default installation packages)
** Dates: 20101110 - 20130221 (835 days)
** 172 advisories (C=9 I=70 L=19 M=74 )
** 546 vulnerabilities (C=23 I=131 L=156 M=236 )

And taken from the last report "Fixed between GA and 6.3 iso":

** Product: Red Hat Enterprise Linux 6 server (all packages)
** Dates: 20101110 - 20120620 (589 days)
** 278 advisories (C=33 I=78 L=31 M=136 )
** 796 vulnerabilities (C=104 I=140 L=196 M=356 )

** Product: Red Hat Enterprise Linux 6 Server (default installation packages)
** Dates: 20101110 - 20120620 (589 days)
** 134 advisories (C=6 I=56 L=15 M=57 )
** 438 vulnerabilities (C=16 I=110 L=126 M=186 )

Therefore between 6.3 iso and 6.4 iso:

** Product: Red Hat Enterprise Linux 6 server (all packages)
** Dates: 20120621 - 20130221 (246 days)
** 108 advisories (C=18 I=28 L=16 M=46 )
** 311 vulnerabilities (C=78 I=41 L=80 M=112 )

** Product: Red Hat Enterprise Linux 6 Server (default installation packages)
** Dates: 20120621 - 20130221 (246 days)
** 38 advisories (C=3 I=14 L=4 M=17 )
** 108 vulnerabilities (C=7 I=21 L=30 M=50 )

Note: although we have 3 default criticals, they are in openjdk-1.6.0, but we only call Java issues critical if they can be exploited via a browser, and in RHEL6 the Java browser plugin is in the icedtea-web package, which isn't a default package. So that means on a default install you don't get Java plugins running in your browser, so really these are not default criticals in RHEL6 default at all.

You can read my Enterprise Linux 6.2 to 6.3 risk report on the Red Hat Security Blog.
"for all packages, from release of 6.2 up to and including 6.3, we shipped 88 advisories to address 233 vulnerabilities. 15 advisories were rated critical, 23 were important, and the remaining 50 were moderate and low."

"Updates to correct 34 of the 36 critical vulnerabilities were available via Red Hat Network either the same day or the next calendar day after the issues were public. The Kerberos telnet flaw was fixed in 2 calendar days as the issue was published on Christmas day. The second PHP flaw took 4 calendar days (over a weekend) as the initial fix released upstream was incomplete."

And if you are interested in how the figures were calculated, as always view the source of this blog entry.

20120928_prime For a two day trip I decided to test using my Android tablet instead of also taking a laptop, and it worked out okay for the most part.

I was booked to go to Red Hat HQ in Raleigh, NC at the start of August for a two-day business trip, well more accurately two-days in the office and another two-days of travelling. I'd usually take my trusty ThinkPad x201 on the trip with me, it's small and light, but it's battery life isn't so great anymore. Earlier this year I'd bought an Android tablet, an ASUS Transformer Prime which with a long battery life would be perfect for movies, but could it replace my ThinkPad completely and save me travelling with two devices? I worked through my requirements and it seemed plausible in theory, so here is how it stacked up in practice:

So in summary I think I got away with it; having just the tablet didn't stop me doing anything that had to be done on the trip and I'll definately do the same thing again in the future for very short trips. For anything more than a couple of days or where connectivity might be an issue I'd miss having a full-featured OS.

We now have an official Red Hat Security Blog, and you'll find all my future reports and discussions about security metrics there. In the meantime here are a few already published articles:

The Common Vulnerability Reporting Framework (CVRF) is a way to share information about security updates in an XML machine-readable format. CVRF 1.1 got released this week and over at Red Hat we've started publishing our security advisories in CVRF format.

Find out more from our FAQ and formatting guide.

When I moved to a new house in 2001 I designed and installed my own home-brew home automation system in it to control things like the heating, lighting, alarm system, and more. The messaging system I picked was to use standard XMPP (Jabber) because most platforms have existing open source XMPP libraries so writing clients is easy. The back-end is just a load of XMPP bots written in Perl. Around the house I had a number of Fujitsu Point 1600 tablets running an interface I designed and wrote using Perl/Tk. The tablets are great, but they're starting to show their age with limited resolution of 800x600 and CPU speed making full-screen video not really possible.

So last year I obtained an Archos 101 10.1" android tablet with the plan being to replace the existing tablets with android powered ones. It was a good excuse to dust off the old skills and learn programming apps for Android. Converting the app was straightforward and tooks a couple of weekends, troubles with the tablet took quite a bit more work.

Finding a way to mount the Archos tablet on a wall proved tricky, the back of the device isn't perfectly flat and it has an annoying desk stand in the middle. I ended up using a PadTab for mounting, but having to custom modify it to handle not being in the centre of the device, and add thick sticky strips (normally used to dampen fans). The build quality of these tablets is pretty poor.


The display panel on the tablet isn't very good either and has limited viewing angles from three sides, so in order to be able to see the screen when mounted to the wall I had to turn it upside down. Android can happily handle a rotated display, the only downside is that the Archos logo is the wrong way up (a bit of black tape covers it up now).

I left the Archos mounted on the wall and running for a week, permanently attached to its charger. At the end of the week I noticed it wasn't sitting straight on the wall, and in fact the internal batteries had both swelled up and burst out of the case. I read online a few other stories from folks who had bought Archos tablets which had failed in the same way, I guess they're really not designed to be left on charge permanently (that's really bad design Archos, this could have easily caught fire!)

I figured I didn't really need to have batteries installed, the tablet is going to be permanently powered on anyway, and it would be safer to leave the house knowing there was no risk of exploding batteries. So I took the tablet apart and removed them. Without batteries the Archos starts its power up cycle, displays a logo, then gets to a certain part of the boot process and powers down. I guess it does a check on the state of the batteries and it fails. This presented a real problem and I gave up trying to use the tablet. Over the Christmas holidays I heard that you could flash an alternative OS, CyanogenMod, and that actually booted and ran just fine without batteries, but it wasn't stable and featured enough for running the Home Automation app I'd written.

So I decided to try to debug the Archos OS, so connected it to USB to get debug messages, and interestingly it powered up perfectly first time. Removing the USB connection caused it to lock up a few seconds later. Strange behaviour! I tried just connecting power to the USB port, and that worked too. So if you want to run your Archos 101 android tablet without internal batteries you can, but you need to splice your power cable and feed 5v to both the power socket and the USB socket.

So now I had a working tablet again I changed the power adaptor so it mounted neatly against the wall:


Here are a couple of pics of it in use:



Red Hat Enterprise Linux 5.8 was released today (February 2012), seven months since the release of 5.7 in July 2011. So let's use this opportunity to take a quick look back over the vulnerabilities and security updates made in that time, specifically for Red Hat Enterprise Linux 5 Server.

Red Hat Enterprise Linux 5 is coming up to its fifth year since release, and is supported for another five years, until 2017.

Errata count

The chart below illustrates the total number of security updates issued for Red Hat Enterprise Linux 5 Server if you had installed 5.7, up to and including the 5.8 release, broken down by severity. It's split into two columns, one for the packages you'd get if you did a default install, and the other if you installed every single package (which is unlikely as it would involve quite a bit of manual effort to select every one). For a given installation, the number of package updates and vulnerabilities that affected you will depend on exactly what packages you have installed or removed.

Number of security errata between
     5.7 and 5.8

So, for a default install, from release of 5.7 up to and including 5.8, we shipped 42 advisories to address 118 vulnerabilities. 4 advisories were rated critical, 13 were important, and the remaining 25 were moderate and low.

Or, for all packages, from release of 5.7 up to and including 5.8, we shipped 71 advisories to address 177 vulnerabilities. 7 advisories were rated critical, 16 were important, and the remaining 48 were moderate and low.

Critical vulnerabilities

The 7 critical advisories addressed 20 critical vulnerabilities across 4 different packages:

  1. An update to OpenJDK 6 Java Runtime Environment, (October 2011) where a web site hosting a malicious Java applet could potentially run arbitrary code as the user.
  2. An update to the MIT krb5 telnet daemon (December 2011) where a remote attacker who can access the telnet port of a target machine could use this flaw to execute arbitrary code as root. Note that the krb5 telnet daemon is not installed or enabled by default, and the default firewall rules block remote access to the telnet port. This flaw did not affect the more commonly used telnet daemon distributed in the telnet-server package.
  3. Updates to PHP and PHP 5.3 (February 2012) where a remote attacker could send a specially-crafted HTTP request to cause the PHP interpreter to crash or, possibly, execute arbitrary code. This flaw was caused by the fix for CVE-2011-4885.
  4. Three updates to Firefox (August 2011, September 2011, November 2011) where a malicious web site could potentially run arbitrary code as the user running Firefox.

Updates to correct 19 out of the 20 critical vulnerabilities were available via Red Hat Network either the same day or the next calendar day after the issues were public. The update to krb5 took 2 calendar days because it was public on Christmas day.

Overall, for Red Hat Enterprise Linux 5 since release until 5.8, 98% of critical vulnerabilities have had an update available to address them available from the Red Hat Network either the same day or the next calendar day after the issue was public.

Other significant vulnerabilities

Although not in the definition of critical severity, also of interest during this period were a couple of remote denial of service flaws that were easily exploitable:

In addition, updates to Firefox, NSS, and Thunderbird were made to blacklist a compromised Certificate Authority.

Previous update releases

To compare these statistics with previous update releases we need to take into account that the time between each update release is different. So looking at a default installation and calculating the number of advisories per month gives the following chart:

Errata per month for each update release

This data is interesting to get a feel for the risk of running Enterprise Linux 5 Server, but isn't really useful for comparisons with other major versions, distributions, or operating systems -- for example, a default install of Red Hat Enterprise Linux 4AS did not include Firefox, but 5 Server does. You can use our public security measurement data and tools, and run your own custom metrics for any given Red Hat product, package set, timescales, and severity range of interest.

See also: 5.7, 5.6, 5.5, 5.4, 5.3, 5.2, and 5.1 risk reports.

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Hi! I'm Mark Cox. This blog gives my thoughts and opinions on my security work, open source, fedora, home automation, and other topics.