The inspiration for the Sonik video for Gravitation came from a local friend of
ours, a talented and world-renowned photographer, Adrian Brannan. Ade is famous for
his analogue photo
collages (please give him a 'like' on his Facebook page):
We
often wondered how the same effect would look if rendered with video. With video
you've got the extra element of time, each segment of the mosaic can be running
from a different starting point, with a different speed, and even a different
direction. In addition the segments themselves can move over time. Would this
end up with an effect that was just too much of a mess? Or would it give an
effect that helps visualise the consequence of spacetime?
We started by taking several videos at three different locations over the period
of a year with a Kodak Zi8 camera. A motorway bridge over the M74, just outside
the Buchanan shopping center in Glasgow, and a bench in Strathclyde park.
Lining up the images was done roughly by using lines drawn on acetate stuck over the
camera screen.
The software to do the mosaic effect was hand-written. We used a simple
scripting language, Perl, and the image library GD. On a relatively modern
Linux PC running Fedora 16 we can render near real-time 720p HD even when handling 300
segments of mosaic. A simple language controls which parts of the screen come
from which video, and the first half of the music video uses this with simple
effects having just a few boxes overlayed:
Later in the video things get more
complicated, using randomisation to pick the location and movement of each
segment:
We used our scripts to create a number of ~13 second segments, then put them all
together using kdenlive. The intro and outro were taken from a different video
from a hotel room in London Victoria; the intro using a 'miniature' effect, and
outro using the randomised segments applied to a single video.
Red Hat Enterprise Linux 6.2 was released this week (Dec 2011), just
over six months since the release of 6.1 in May 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 6 Server.
Errata count
The chart below illustrates the total number of security updates issued for Red
Hat Enterprise Linux 6 Server if you had installed 6.1, up to and including the
6.2 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 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 you
have installed or removed.
So, for a default install, from release of 6.1 up to and including 6.2, we
shipped 36 advisories to address 121 vulnerabilities. 2 advisories were rated
critical, 10 were important, and the remaining 24 were moderate and low.
Or, for all packages, from release of 6.1 up to and including 6.2, we shipped
88 advisories to address 218 vulnerabilities. 10 advisories were rated critical,
16 were important, and the remaining 62 were moderate and low.
Critical vulnerabilities
The 10 critical advisories addressed 31 critical vulnerabilities across 3 components:
Two updates to the OpenJDK 6 Java Runtime
(June 2011,
October 2011)
where a malicious web site presenting a Java applet could potentially run arbitrary code as the user
running a web browser.
Updates to correct all of the 31 critical vulnerabilities were
available via Red Hat Network either the same day or the next calendar
day after the issues were public.
Other significant vulnerabilities
Although not in the definition of critical severity, also of interest during
this period were a few flaws that were high risk or easily exploitable:
A flaw in Bind, CVE-2011-4313
fixed by RHSA-2011:1458
where a malicious client could cause Bind to stop responding, a denial
of service attack. This flaw was discovered by it being accidentally
triggered in the wild.
A flaw in the Apache HTTP Server, CVE-2011-3192,
fixed by RHSA-2011:1245, where a remote attacker could
cause a denial of service attack. This was discovered due to a public exploit.
A flaw in RPM, CVE-2011-3378
fixed by RHSA-2011:1349
where a specially-crafted RPM package that, when queried or installed,
would cause rpm to crash or, potentially, execute arbitrary code prior to any
signature checking. We're not aware of any working exploits for this issue.
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:
This data is interesting to get a feel for the risk of running Enterprise
Linux 6 Server, but isn't really useful for comparisons with other major
versions, distributions, or operating systems -- for example, a default install
of either Red Hat Enterprise Linux 4AS and 6 Server does not include Firefox, but a
default install of 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.
When we get notified of a security issue affecting a Red Hat product
in advance we give an acknowledgement in the security advisory and in our
CVE database.
We've now created a
page to give acknowledgements to the companies and individuals that
report issues in our online services, such as finding a cross-site scripting
flaw in a Red Hat web site, or a vulnerability in OpenShift.
We pushed an
update to Flash Player for Red Hat Enterprise Linux Supplementary today, on
a Friday, because it fixed Critical vulnerabilities. But we try not to push
updates on a Friday unless they are critical and already public.
So let's take a look at the most common times and days we push
advisories for Red Hat Enterprise Linux 4, 5, and 6 (including
Supplementary) using a heatmap:
The more advisories pushed for a given date and hour, the darker
that section of the graph is. So the most popular times
for pushing advisories are Tuesdays at 10am and 2pm Eastern US time,
Fridays are pretty light for pushes, and there was nothing
during the weekends. The spread of the graph shows that we push advisories when
they are ready, rather than waiting to a fixed day and time, in order to reduce
the risk to users.
All the data used to create this graph is available as part of
our public metrics.
Thanks to Sami Kerola for
the R code from which I based my
graph generation.
For my Birthday my wife bought me
a Peggy 2
kit, and I finally got around to adding the 625 10mm green LEDs. Some of the
example programs are pretty neat but I wanted to make a side scroller with
a nice font ready for halloween.
I decided on the Liberation Sans Narrow font, drew up a string of characters in
The Gimp, converted it to have only 4 levels, then used a quick perl script to
convert the image into program data for the scroller. I'm pretty happy with
how it turned out. The scroller, image, and script are available here.
Every year since Red Hat Enterprise Linux 4 was released we've
published a risk report where we look at the state of security
of the distribution. We investigate the key vulnerabilities,
metrics on vulnerability counts, and how users could have been
exploited by them. The
Six
Years
of Red Hat Enterprise Linux 4 report (PDF) covering Feb 2005-2011
was published today.
"Red Hat knew about 51.5% of the security vulnerabilities
that we fixed in advance. The
average time between Red Hat knowing about an issue and it being made
public was 23 days (median 10 days).... A default installation of Red
Hat Enterprise Linux 4 AS was vulnerable to 20 critical security
issues over the first six years. "
The data we publish is interesting to get a feel for the risk of running
Enterprise Linux, but isn't really useful for comparisons with other
distributions, or operating systems. One important difference is that it is Red
Hat policy to count vulnerabilities and allocate CVE names to all issues that
we fix, including ones that are found internally. This is not true for many
other vendors including folks like
Microsoft
and
Adobe
who do not count or disclose issues they fix which were found internally.
A few weeks ago the 2011 update to
the CWE/SANS Top 25 Most Dangerous
Software Errors was published. As part of our contribution to this
update we analysed the most severe vulnerabilities that affected Red Hat
since the last update and mapped each one to the appropriate Common
Weakness Enumeration (CWE) type.
The table below lists all vulnerabilities which have a CVSS score of 7
or more ('high'), that we fixed in any product during calendar year 2010.
Most common CWE were:
Buffer Copy without Checking
Size of Input
(CWE-120): 8 vulnerabilities.
Red Hat Enterprise Linux 5.7 was released last week (July 2011), six months
since the release of 5.6 in January 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.
Errata count
The chart below illustrates the total number of security updates issued for Red
Hat Enterprise Linux 5 Server if you had installed 5.6, up to and including the
5.7 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.
So, for a default install, from release of 5.6 up to and including
5.7, we shipped 27 advisories to address 109 vulnerabilities. 3
advisories were rated critical, 12 were important, and the remaining
12 were moderate and low.
Or, for all packages, from release of 5.6 to and including 5.7, we
shipped 58 advisories to address 172 vulnerabilities. 4 advisories
were rated critical, 20 were important, and the remaining 34 were
moderate and low.
Critical vulnerabilities
The 4 critical advisories addressed 34 critical vulnerabilities across just 2 different packages:
An update to OpenJDK 6 Java Runtime Environment,
(June 2011)
where a web site hosting a malicious Java applet could potentially run
arbitrary code as the user.
Three updates to Firefox (March 2011, April 2011, June 2011)
where a malicious web site could potentially run arbitrary code as the user
running Firefox.
Updates to correct all of the 34 critical vulnerabilities were
available via Red Hat Network either the same day or the next
calendar day after the issues were public.
Overall, for Red Hat Enterprise Linux 5 since release until 5.7, 97%
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 flaws that were easily exploitable:
A flaw in dhcp,
CVE-2011-0997,
fixed by
RHSA-2011:0428, where a malicious DHCP
server could send a response that could lead to arbitrary code execution on connecting clients.
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:
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.
Red Hat has an unrivaled security record when it comes to addressing
security flaws in our products. We reduce the risk to customers using
our products by constantly monitoring for vulnerabilities and threats,
triaging their impact to our customers, and addressing those that
matter the most quickly. The Red Hat Security Response Team are
responsible for dealing with security vulnerabilities in Red Hat
products and services and has a team spanning nine countries.
We've currently got three positions in the team currently open. One
is focused on Java (JBoss) technologies, another on our new Cloud
services, and a final one on our Enterprise Linux product.
Would you like to be part of our dynamic team, and help protect Red
Hat's customers and the open source community as a whole from security
vulnerabilities?
Each of the positions are challenging and demanding; every day you'll
be investigating different issues affecting different products and
codebases, having to manage your time on the issues with the greatest
impact.
Some of the tasks of the job include (but are not limited to):
Rapidly responding to new security issues. You'll need to be able
to think fast, analyze complex problems, use your judgement to assess
vulnerability severities and risks, and switch your priorities to
ensure that serious issues get immediate attention.
Investigating how security flaws specifically impact your
products. Research how the flaws can be exploited by
attackers; by code analysis, testing exploits, or writing proof of
concept tests.
Communicating about flaws with our software developers, managers,
quality engineers, upstream project developers, as well as our peers
in the security response teams of other vendors.
Developing advice and technical documentation for security advisories.
Responsibility for tracking vulnerabilities through the entire
update release lifecycle and ensuring that customers get the right
fixes with the right advice at the right time.
We can be flexible with working location. So if this interests you, email me
a CV/resume (to mjc at redhat.com) as not all the jobs are on our careers page
yet.
Red Hat Enterprise Linux 6.1 was released this week (May 2011), just
over six months since the release of 6.0 in October 2010. 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 6 Server.
Errata count
The chart below illustrates the total number of security updates issued for Red
Hat Enterprise Linux 6 Server if you had installed 6.0, up to and including the
6.1 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 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 you
have installed or removed.
So, for a default install, from release of 6.0 up to and including 6.1, we
shipped 54 advisories to address 195 vulnerabilities. 2 advisories were rated
critical, 29 were important, and the remaining 23 were moderate and low.
Or, for all packages, from release of 6.0 up to and including 6.1, we shipped
102 advisories to address 345 vulnerabilities. 8 advisories were rated critical,
39 were important, and the remaining 55 were moderate and low.
These figures include 10 advisories we released on the day we shipped
6.0. This was because we froze package updates some months before
releasing the product. Two of those updates were rated critical,
an update to Firefox, and to Samba.
Critical vulnerabilities
The 8 critical advisories addressed 37 critical vulnerabilities across 4 components:
An update to Samba (October 2010)
where a malicious client could potentially run arbitrary code as the Samba
server. Samba is a default install package but the server is not enabled by default.
Two updates to Thunderbird (March 2011, April 2011)
where a malicious email message could potentially run arbitrary code as the user
running Thunderbird.
An update to Pango (March 2011)
where an application using Pango to parse untrusted font data (such as
Firefox) could potentially run
arbitrary code as the privileges of the user. Pango is a default install package.
Updates to correct all of the 37 critical vulnerabilities were
available via Red Hat Network either the same day or the next calendar
day after the issues were public.
This data is interesting to get a feel for the risk of running Enterprise
Linux 6 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 and 6 Server 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.
Hi! I'm Mark Cox. This blog gives my
thoughts and opinions on my security
work, open source, fedora, home automation,
and other topics.
For my Birthday my wife bought me
a 
Red Hat has an unrivaled security record when it comes to addressing
security flaws in our products. We reduce the risk to customers using
our products by constantly monitoring for vulnerabilities and threats,
triaging their impact to our customers, and addressing those that
matter the most quickly. The Red Hat Security Response Team are
responsible for dealing with security vulnerabilities in Red Hat
products and services and has a team spanning nine countries.
