Category Archives: Security

Fighting Big (Data) Brother

When I was a full-time student of Cold War history I had to study how the constant watch by an unknown yet omnipresent force affected people. In American classrooms that meant asking questions about the legacy of the 1968 Prague Spring or trying to prove whether Marshal Josip Broz Tito was really as popular as reported publicly.

If you clicked on the links above you will see that I believe some of the best sources for an answer could be from literary and artistic writers. There are classics like The Trial by Kafka and 1984 by Orwell, but we also gain excellent insights from modern work such as The Lives of Others by Donnersmarck.

The real story, however, is not just about the situation in someone else’s backyard. Surveillance society is a risk everywhere and is inextricably linked to advances in communication. It thus seems inevitable to find warnings at home of a “double-edge” to technology. A good example is the historic criticism by U.S. Senator Frank Church of an American-based system meant to spy on the Soviets.

“…this capability at any time could be turned around on the American people” he said in 1975, “and no American would have any privacy left, such is the capability to monitor everything: telephone conversations, telegrams, it doesn’t matter. There would be no place to hide.”

He added that if a dictator ever took over, the N.S.A. “could enable it to impose total tyranny, and there would be no way to fight back.

He was wrong. A dictator is not necessary to achieve what many would consider tyranny, at least if you take into account definitions put forward by the likes of Kafka and Orwell. And the N.S.A. giant spy center is not the only one to consider.

He also was right. The capability officially has been turned around on the American people.

CNET has learned that the FBI has formed a Domestic Communications Assistance Center, which is tasked with developing new electronic surveillance technologies, including intercepting Internet, wireless, and VoIP communications.

And that brings me back to the study of surveillance in the Cold War. The British classroom forced me to expand the scope of discussion. We had to spend many hours debating and trying to make sense of policies all over the world where analysts collected data on citizens to enforce laws and inform leaders. One of the things that stood out to me was how citizen behavior altered in some versions of surveillance, but not others. The difference appeared to me linked to a sense of value and opportunity.

If collection of information is in any way perceived by an individual as a threat to their success then countermeasures are a natural reaction. It was only when risk from surveillance was not perceived (e.g. “I have nothing to hide”), or a greater alternate threat was proposed (e.g. surveillance will save you from a worse fate) that someone might be expected to comply without question.

What countermeasures? We destroy a trail or hide it. In terms of security, people use integrity and confidentiality controls to fight surveillance. The tricky part is that we enjoy and want social approval; it gives the ability to see a more circumspect view. But on the other hand we do not want to feel as though we are being monitored to the point where we are boxed in by our every decision (i.e. the dilemma of whether to have a heavy or light existence, as expressed in the Unbearable Lightness of Being)

Countermeasures might not always be the right term. I am reminded of Manuel Castells’ 1996 book The Rise of the Network Society. He emphasized that a globally interconnected communication system was unlikely to make a work force go completely mobile. He showed that people prefer to keep local social attachment (e.g. owning a house, living near family and friends) intact. However, other social structures such as labor relationships were not as stable. They could evolve because more opportunities would be available and it would make part-time and temporary work the norm.

Thus, rather than call them countermeasures, we tend to keep only trails intact where we perceive value and limited risk. Cycling through connections when more connections are offered at low cost becomes a new norm, which can cause problems for those interested in data collection and analysis.

With that in mind, I noted recently big data researchers saying that their subjects are fighting back.

Ms. Boyd has made a specialty of studying young people’s behavior on the Internet. She says they are now often seeking power over their environment through misdirection, such as continually making and destroying Facebook accounts, or steganography, a cryptographic term for hiding things in plain sight by obscuring their true meaning. “Someone writes, ‘I’m sick and tired of all this,’ and it gets ‘liked’ by 32 people,” she said. “When I started doing my fieldwork I could tell you what people were talking about. Now I can’t.”

Now. Just like in history. The behavior she describes sounds like exactly what could be expected in a surveillance society that has a low cost to connection cycles. What does this mean in terms of future behavior? It’s not clear who the best artistic writers will be yet but there may be much more lightness ahead.

For example, in the past there was a desire in America to make a phone number portable to maintain continuity across providers, but the new trend appears to be more like what Castells predicted and numbers have short-term or temporary use. Another example is demand for peer-based key management, instead of server, for mobile devices. A third example is demand for sandboxes and hypervisors to create safe havens of communication. Hiding or destroying the trail of an application, a machine or even an entire data center, is more possible than ever through virtualization.

Ok, enough with the MD5 already

Today in a meeting I referenced a 2007 paper by Arjen Lenstra and Benne de Weger on how to break MD5 to abuse vendor software updates.

Here it is again for convenience:

Given the recent insights into the weaknesses of MD5, the bottomline of our work is: MD5 should no longer be used as a hash function for software integrity or code signing purposes. By now, everyone should be aware of this.

The paper also explained why their collisions were different from before.

In December 2004 Dan Kaminsky and Ondrej Mikle, and later Peter Selinger, published similar attacks, based on the Wang-type collisions that require two binary files that differ only in the colliding blocks. To create such files from two executables with different behaviour that yet collide under MD5, each of the two files has to contain both executables in full, somehow using the collision to switch on the one and hide the other.

Our colliding files are based on chosen-prefix collisions. This means that we only have to append a few thousand carefully chosen bytes to each file to reach an MD5 collision. Each file by itself contains only one of the two executables. This is less suspicious.

And we also knew in 2007, in terms of real-world data, that Google could easily show collisions were far more common than one might expect.

Fast forward to today and it is like some people completely missed five years of warnings.

…the collision attacks observed in Flame could have been prevented if Microsoft had stopped employing MD5 sooner.

Whether or not you buy into the big compute-power argument or the attack sophistication argument for Flame (neither of which are well quantified) since 2007 the message has been to stop using MD5 for trust.

CVE-2012-2118: X.org input device format string

The xorg-x11-server log may have a format string flaw in certain forms of its log message. An attacker would have to give a device a specific name and then get the local Xorg server instance to use it for the flaw to cause the server to abort or malfunction.

IBM rated this vulnerability high risk yet gave it a base score of 4.4

X.org could allow a local attacker to execute arbitrary code on the system, caused by a format string error when adding an input device with a malicious name. By persuading a victim to open a specially-crafted file containing malicious format specifiers, a local attacker could exploit this vulnerability to execute arbitrary code on the system or cause the application to crash.

NIST gives it a perfect 10, however.

Access Vector: Network exploitable
Access Complexity: Low
Authentication: Not required to exploit
Impact Type: Allows unauthorized disclosure of information; Allows unauthorized modification; Allows disruption of service

The flaw is explained on Patchwork

The culprit here was not the user-supplied format string but rather xf86IDrvMsg using the device’s name, assembling a format string in the form of

 [driver]: [name]: message[/name][/driver]

i.e. “evdev: %n%n%n%n: Device \”%s\”\n”
and using that as format string to LogVWrite.

I also mentioned a serious vulnerability related to evdev in an earlier post.

…crash is related to changing the driver for input devices using evdev (xserver-xorg-input-evdev) — the kernel event delivery mechanism that handles multiple keyboards and mice as separate input devices

Terrorist Use of Fire as a Weapon

I have had several people ask about the possibility of terrorist activity related to the Colorado fires. There are two main factors to explore at this point. Recent intelligence reports coupled with the evidence of arson in proximity of inhabited areas make it impossible to rule out terrorism.

Intelligence reports

Terrorist groups on May 2nd, 2012 published details on how to use fire as a weapon, as reported by ABC news on May 3rd.

Several days later, on May 7th, 2012, the Denver Division of the FBI released a Criminal Activity Alert to raise awareness about wildfires and Al-Qaida. It mentioned the terrorist group was monitoring for the right conditions, such as high winds and dryness, to spread fires. By the end of the month a Homeland Security / DHS report was issued called “Terrorist Interest in Using Fire as a Weapon.”

For at least a decade, international terrorist groups and associated individuals have expressed interest in using fire as a tactic against the Homeland to cause economic loss, fear, resource depletion, and humanitarian hardship. There is no evidence that international terrorist groups and inspired individuals are responsible for any purposeful destruction of public or private property by setting wildfires in the United States. Using fire as a weapon, however, is inexpensive and requires limited technical expertise, giving it a strong advantage over other methods of attack. Statements advocating this tactic are most often found on violent extremist Web forums and in violent extremist propaganda.

[…]

We have no indications AQAP or unaffiliated violent extremists are planning to act upon the suggestions contained in Inspire.

[…]

We do not have any current intelligence indicating terrorists or violent extremists in the United States are planning to use fire as a weapon as described in Inspire magazine and online violent extremist forums. However, because terrorists have long shown interest in this tactic, which is inexpensive, low risk, and requires little technical knowledge, we encourage first responders to remain vigilant to indicators of the potential use of fire as a weapon

Evidence of Arson

It is not clear whether it is by “inspired individuals” or terrorists but reports indicate human fault during the exact conditions mentioned by the FBI.

Fire investigators believe the fire was sparked by someone participating in recreational shooting over the weekend, possibly by people shooting a gun at a fuel tank.

The latest Detailed Situation Report from the Geographic Area Coordination Center (GACC) for the Rocky Mountains (RMCC) has the following data showing rapid spread of fires in populated areas:

New Fires: 18
Acres: 54,105
Uncontrolled Fires: 7

InciWeb shows the proximity of the Waldo fire to Colorado Springs, forcing the evacuation of more than 30,000.

Here are recent photos taken by Phillip Smith in the Colorado Springs area

The GACC Large Incident Report gives current estimates such as the following:

Waldo Canyon Structures Threatened: 20,085 PRIM , 160 COMM
Waldo Canyon Costs to Date: $1,950,194
High Park Structures Threatened: 1,969 PRIM , 6 COMM
High Park Structures Destroyed: 257 PRIM , 52 OUTB
High Park Costs to Date: $33,100,000

Although these numbers are incredibly large and show the fires to be disastrous, the Incident Information System and National Interagency Fire Center puts them in context of national activity.

Large fire activity increased yesterday as 15 new large fires were reported: four in Montana, three in Alaska and Alabama, and one in Arizona, Colorado, New Mexico, Utah and Wyoming. Firefighters contained five large fires, including the Dump and Grease fires in Utah.

[…]

10 Year Average 2003-2012
Fires: 36,407
Acres: 1,931,551

The large fire data across the western states corresponds with their map of high risk areas.

It can also be compared to the current Large Fire Incidents map from the USDA Forest Service Active Fire Mapping Program.

So there is a strong correlation of intelligence data with evidence of arson, but cause still needs to be fully investigated.