31 ms·

The NSA developed their own networking protocol, separate from TCP or UDP, which operates just above the physical layer. The idea is that you rewrite the netwo

by shawn 8y ago

The NSA developed their own networking protocol, separate from TCP or UDP, which operates just above the physical layer. The idea is that you rewrite the network card firmware so that there’s an NSA MITM running on it. The host computer never knows, because as far as the computer is concerned the network card is sending exactly the data you would expect. And even if you hook up network monitoring tools externally, you wouldn’t be able to notice anything wrong apart from a slightly reduced total bandwidth. The value of such a tool is that it can be installed remotely, with no physical presence. They also have all kinds of gadgets to defeat airgaps. IIRC one of them was a replacement keyboard that looks identical to the normal one, but provides the stealth wifi you mention. One way to get an idea of what the NSA is up to is to look at their job listings. They can fake everything else, but not those.

cozzyd 8y ago
Why wouldn't an organization fake their job postings to lead people astray? Like if the FSB started hiring string theorists or telekinesthetics positions to waste the NSA's time figuring out why they're doing that.
- defen 8y ago
  > Like if the FSB started hiring string theorists or telekinesthetics positions to waste the NSA's time figuring out why they're doing that. They already did that: https://www.atlasobscura.com/articles/nikolai-khokhlov-kgb-paranormal https://www.atlasobscura.com/articles/nikolai-khokhlov-kgb-p...
Cyph0n 8y ago
> which operates just above the physical layer. So at the link layer? If so, what you described does not sound like an effective technique to exfiltrate data over the internet, unless the NSA also controls the LAN/internal network the target device is on. Why? Because any non-standard protocol data will be thrown out by the first switch or router on the path out of the target LAN. In other words, the exfiltrated data will not be forwarded on to the next router or switch, simply because the next router/switch will not have support for the NSA's custom protocol in its network stack.
- shawn 8y ago
  One thing the NSA is very good at is getting access to virtually every type of networking card. If they achieve access to a target, it's likely they control a path to it. If the target is a wifi device, the custom protocol becomes doubly effective: Exfiltration is a matter of having a receiver anywhere in the vicinity. And that receiver can amplify the signal to blast it a few miles. There are tools to sweep the EM spectrum looking for anomalies like this, but they seem to be rare, for the moment.
  - viraptor 8y ago
    > If they achieve access to a target, it's likely they control a path to it. Without specific, documented cases this is speculation of course. But I don't see why they'd use a link level protocol. 1. It requires patching multiple networking devices in the path, which is not very quiet. 2. It sticks out in any monitoring (via mirror ports) more than a UDP packet to a random host. DNS or ntp as a transport would be much simpler to hide.
    - amoshi 8y ago
      And what exactly would be the problem for the NSA with patching networking devices? They even mention how it's useful specifically for these hard targets >"some of the most productive operations in TAO because they pre-position access points into hard target networks around the world." https://arstechnica.com/tech-policy/2014/05/photos-of-an-nsa-upgrade-factory-show-cisco-router-getting-implant/ https://arstechnica.com/tech-policy/2014/05/photos-of-an-nsa...
- Bromskloss 8y ago
  Could packet delays perhaps survive over the network?
  - nickpsecurity 8y ago
    Yes. I used both header fields and delays as covert channels in the past since I know security professionals never looked for them. I derived them by just applying a standard, covert-channel analysis on the protocol. Others have described some methods publicly: https://defcon.org/images/defcon-10/dc-10-presentations/dc10-hintz-covert.pdf https://defcon.org/images/defcon-10/dc-10-presentations/dc10... https://engineering.purdue.edu/dcsl/publications/papers/2009/timingchannel_infocom09_submit.pdf https://engineering.purdue.edu/dcsl/publications/papers/2009... The oldest methods of finding stuff like this are Kemmerer's Shared Resource Matrix (1983) for storage channels and Wray's updated characterization (1991) that were used in DOD's security certification (TCSEC). They work for hardware, too, since it's how they found cache-based, timing channels in hardware hosting the VAX Security Kernel in 1992. http://www.cs.ucsb.edu/~sherwood/cs290/papers/covert-kemmerer.pdf http://www.cs.ucsb.edu/~sherwood/cs290/papers/covert-kemmere... http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.534.7024 http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.534.... For transport, military-grade security often mandated fixed-size, fixed-rate transmission with error handling itself not able to leak stuff. Tricky on error part, inefficient other part. A primitive software defense is to clear the storage channels while throttling and randomizing the timing of delivery. Works best on non-real-time or already-slow configurations. Idea fit for store-and-forward messaging, which was preferred for high-assurance security. Another option from 1990's high security was to have a PCI card or something running a security kernel do the actual transfer from a labeled source. As in, the source can be as malicious as it wants with it unlikely to effect secure kernel. The kernel might prevent it, detect it, shut it down, or preserve logs for traceability. There was also the "force everything over link/network encryptor" concept to attempt to cheat. Leaves some metadata which can be mitigated or obfuscated by other means including prior transmission method. Hope that helps. Current work uses models or languages to track shared resources for automatically detecting storage or timing channels among other things. I'll dig some out of my collection if anyone wants them.
fooker 8y ago
Do you have a source for this claim?
- secfirstmd 8y ago
  Exactly my question!
secfirstmd 8y ago
Interesting....source?
jonhendry18 8y ago
" They can fake everything else, but not those." They could hire through front companies, obfuscating the connection to the NSA.

by shawn 8y ago

cozzyd 8y ago

Why wouldn't an organization fake their job postings to lead people astray? Like if the FSB started hiring string theorists or telekinesthetics positions to waste the NSA's time figuring out why they're doing that.

defen 8y ago
> Like if the FSB started hiring string theorists or telekinesthetics positions to waste the NSA's time figuring out why they're doing that. They already did that: https://www.atlasobscura.com/articles/nikolai-khokhlov-kgb-paranormal https://www.atlasobscura.com/articles/nikolai-khokhlov-kgb-p...

Cyph0n 8y ago

> which operates just above the physical layer. So at the link layer? If so, what you described does not sound like an effective technique to exfiltrate data over the internet, unless the NSA also controls the LAN/internal network the target device is on. Why? Because any non-standard protocol data will be thrown out by the first switch or router on the path out of the target LAN. In other words, the exfiltrated data will not be forwarded on to the next router or switch, simply because the next router/switch will not have support for the NSA's custom protocol in its network stack.

shawn 8y ago
One thing the NSA is very good at is getting access to virtually every type of networking card. If they achieve access to a target, it's likely they control a path to it. If the target is a wifi device, the custom protocol becomes doubly effective: Exfiltration is a matter of having a receiver anywhere in the vicinity. And that receiver can amplify the signal to blast it a few miles. There are tools to sweep the EM spectrum looking for anomalies like this, but they seem to be rare, for the moment.
- viraptor 8y ago
  > If they achieve access to a target, it's likely they control a path to it. Without specific, documented cases this is speculation of course. But I don't see why they'd use a link level protocol. 1. It requires patching multiple networking devices in the path, which is not very quiet. 2. It sticks out in any monitoring (via mirror ports) more than a UDP packet to a random host. DNS or ntp as a transport would be much simpler to hide.
  - amoshi 8y ago
    And what exactly would be the problem for the NSA with patching networking devices? They even mention how it's useful specifically for these hard targets >"some of the most productive operations in TAO because they pre-position access points into hard target networks around the world." https://arstechnica.com/tech-policy/2014/05/photos-of-an-nsa-upgrade-factory-show-cisco-router-getting-implant/ https://arstechnica.com/tech-policy/2014/05/photos-of-an-nsa...
Bromskloss 8y ago
Could packet delays perhaps survive over the network?
- nickpsecurity 8y ago
  Yes. I used both header fields and delays as covert channels in the past since I know security professionals never looked for them. I derived them by just applying a standard, covert-channel analysis on the protocol. Others have described some methods publicly: https://defcon.org/images/defcon-10/dc-10-presentations/dc10-hintz-covert.pdf https://defcon.org/images/defcon-10/dc-10-presentations/dc10... https://engineering.purdue.edu/dcsl/publications/papers/2009/timingchannel_infocom09_submit.pdf https://engineering.purdue.edu/dcsl/publications/papers/2009... The oldest methods of finding stuff like this are Kemmerer's Shared Resource Matrix (1983) for storage channels and Wray's updated characterization (1991) that were used in DOD's security certification (TCSEC). They work for hardware, too, since it's how they found cache-based, timing channels in hardware hosting the VAX Security Kernel in 1992. http://www.cs.ucsb.edu/~sherwood/cs290/papers/covert-kemmerer.pdf http://www.cs.ucsb.edu/~sherwood/cs290/papers/covert-kemmere... http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.534.7024 http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.534.... For transport, military-grade security often mandated fixed-size, fixed-rate transmission with error handling itself not able to leak stuff. Tricky on error part, inefficient other part. A primitive software defense is to clear the storage channels while throttling and randomizing the timing of delivery. Works best on non-real-time or already-slow configurations. Idea fit for store-and-forward messaging, which was preferred for high-assurance security. Another option from 1990's high security was to have a PCI card or something running a security kernel do the actual transfer from a labeled source. As in, the source can be as malicious as it wants with it unlikely to effect secure kernel. The kernel might prevent it, detect it, shut it down, or preserve logs for traceability. There was also the "force everything over link/network encryptor" concept to attempt to cheat. Leaves some metadata which can be mitigated or obfuscated by other means including prior transmission method. Hope that helps. Current work uses models or languages to track shared resources for automatically detecting storage or timing channels among other things. I'll dig some out of my collection if anyone wants them.

fooker 8y ago

Do you have a source for this claim?

secfirstmd 8y ago
Exactly my question!

secfirstmd 8y ago

Interesting....source?

jonhendry18 8y ago

" They can fake everything else, but not those." They could hire through front companies, obfuscating the connection to the NSA.