9 ms·

The author does not seem to understand the engineering background. Security should not be trusted on such a low layer of the network stack. No matter which att

The author does not seem to understand the engineering background. Security should not be trusted on such a low layer of the network stack. No matter which attacker we want protection against, the points to secure are client and server, not the middle-boxes. This is one of the well known reasons HTTP/2 is implemented by browser vendors only on a secure channel. Here we are talking about implementing security in hardware (bad idea: hard to upgrade as security requirements and practices chage) at a very low level (at data link layer). If this is to skip security at higher levels of the stack, you have to trust all hardware vendors and operators worldwide. If we don't, we can as well communicate on an insecure channel: that's what modern TLS provides. Of course to get all users to use only secure channels is a lot of work, it's just that there is no easier alternative that provides this same result. Granted, the author might have something else in mind: he might want communication to be safe only against some parties, but not others.

lgierth 8y ago
I agree that the security of communication between endpoints mustn't be trusted to the lower layers, but this is only the application layer. The network itself needs to be secured just as well -- thinking especially of SS7 and BGP and the likes here.
- dullgiulio 8y ago
  Good point. With BGP you can cause a denial of service. But again, TLS should reduce the risk to just that and nothing worse (intercepted/counterfait information.)
  - bdamm 8y ago
    This isn't just about preventing denial of service. It's also about preventing direct attacks to your phone's base-band controllers. It's also about reducing the leverage attackers have to manipulate weak applications.
- tptacek 8y ago
  The error here is in think of security as something you have or don't have. But of course, it doesn't work like that. Security is an economic problem. You deploy countermeasures to raise the cost of an effective attack beyond what rational or realistic attackers will be willing to pay. What does that mean for SS7? It's a little tough to say: you have to peel off all the layers above and below it and factor out the security they provide, and then map what's left to attacks that are meaningful to realistic attackers. All this is to say, the kind of security most people think about when they discuss 5G and SS7 security --- universally trustworthy cryptographic secure channels --- is not a good fit. I tend to think the same thing about BGP (vis a vis global signing schemes like RPKI), but I recognize that I'm an oddball in that regard.
  - freedomben 8y ago
    I tend to agree with you, tho when I consider security of the 5G network I think more about large-scale disruptions due to compromise rather than targeting of individuals. Example scenario: War breaks out between two nations (such as the US and China, or US and Russia, or some other country). Cyber attack from enemy shuts down many if not all wireless communication. That would be a catastrophic disaster, and something that does seem like a legitimate defense consideration. That said, I tend to think that free and mutually dependent trade is a good solution here (basically the opposite of Trump's trade war). Going back to the ancients, the countries with the most trade are the least likely to engage in hostile acts. There's an old saying, "where goods cross borders, armies don't."
    - mycall 8y ago
      This is where mesh networking comes into play for LWAN fallback.
peterwwillis 8y ago
> No matter which attacker we want protection against, the points to secure are client and server, not the middle-boxes. > Here we are talking about implementing security in hardware (bad idea: hard to upgrade as security requirements and practices chage) at a very low level (at data link layer). If this is to skip security at higher levels of the stack, you have to trust all hardware vendors and operators worldwide. If we don't, we can as well communicate on an insecure channel: that's what modern TLS provides. So you're turning off WPA on your wireless router, I take it? TLS is not a panacea, and there are many attack vectors for devices and applications throughout the entire network path. Defense in depth suggests security be applied wherever there is a vector.
- kstenerud 8y ago
  You turn on WPA to stop other people from using your WIFI, and to provide a minimum level of protection for your non-encrypted communications (legacy apps). And, of course, every few years the current wireless protection systems are defeated, rendering the whole thing useless until you upgrade your hardware (because nobody wants to spend money to provide a software fix for something you've already bought).
  - zamadatix 8y ago
    The same could be said for TLS, this seems like you're strengthening the argument of defense in depth.
    - kstenerud 8y ago
      Tls is better than nothing, but still not that great. The best would be per app end to end encryption, but that would be a ton of work, and suffer from each implementations mistakes, so you're left with a trade-off between security and doability.
  - deleted 8y ago
    [deleted]
gruez 8y ago
By that logic, we shouldn't bother securing wifi APs because everything's encrypted at the application layer anyways. Also, AFAIK SMS and VoLTE don't have additional encryption, so if the data layer is compromised, so are those services.
- gcb0 8y ago
  well, people do use wifi from hotels and airbnb...
  - deleted 8y ago
    [deleted]
  - gruez 8y ago
    In that case, having secure/unsecure wifi doesn't really change the equation because the operator itself can still be hostile, even if the link is secure. Having secure (eg. WPA enterprise) wifi only means that some random guy can't intercept your traffic. However, at home, having a secure network is definitely important because of legacy protocols (SMB) or unsecured services (LAN facing http servers)
- y0ghur7_xxx 8y ago
  > By that logic, we shouldn't bother securing wifi APs because everything's encrypted at the application layer anyways. Sure. Why not? I do banking and I read my email on public, untrusted networks like airport and hotel wifi, Starbucks and the internet. I see not problem with that.
  - syn0byte 8y ago
    Public & untrusted != Unencrypted. Otherwise TLS ain't doing shit for you if I control everything you see at layer 2 and up, including the encryption keys and their validity. Would you care to try doing your banking over my WEP-only secured 802.11b network?
    - y0ghur7_xxx 8y ago
noselasd 8y ago
You have to have security at that level as well. The protocol stack services that maintains the radio links to cell towers are client and servers, other parts are between the cell phone and the mobility management node are client and servers. These are services you as a cell phone user don't interact with directly, but still very important as they provide authentication of the user and (ideally and hopefully) authentication of the network, access or indication of your location, and other neccesary services needed to seamless move between cell towers.
- move-on-by 8y ago
  yup, its called defense-in-depth
okl 8y ago
The author does not care about security, he cares about increasing funding and power of the FCC. > Mr. Wheeler is a former chairman of the Federal Communications Commission.
- archgoon 8y ago
  One can both be a former chairman of the FCC and care about security. I think you need to expand on your argument to justify your claim. Has the author previously opposed pro security proposals?
  - okl 8y ago
    Yes, you are right.
mtgx 8y ago
Still, it would've been nice if the new RCS messaging system would've had end-to-end encryption by default. Or at least that 5G got strong protection against Stingrays. But we all know why none of that happened. The wireless network protocols are designed with the "help" of the world's top intelligence agencies (and no, that's not so we can benefit from the additional security).
BostonEnginerd 8y ago
I disagree with you - security is important at all layers of the stack. Right now, your mobile phone will connect to fake towers (Stingray). This means that SMS 2FA codes can be intercepted to you, I believe. https://nakedsecurity.sophos.com/2018/04/06/washington-dc-awash-with-fake-cell-towers/ https://nakedsecurity.sophos.com/2018/04/06/washington-dc-aw...
- silvestrov 8y ago
  No, the problem is that the SMS standard was never updated with an encrypted version. Apple didn't want to open iMessage to the world. EU/USA should enforce a common, secure method for sending text messages to mobiles.
  - simias 8y ago
    I agree with your main point but I feel like SMS is going to remain cleartext forever. It's basically like email (it's not like encrypted email formats ever gained mainstream traction). Besides I can't really imagine the EU/USA pushing for end-to-end SMS encryption. Fortunately as data plans get cheaper we have plenty of alternatives for encrypted messaging on smartphones.
    - dbdjfjrjvebd 8y ago
      Didn't the UK prevent SMS encryption when the standard was developed?
  - wyldfire 8y ago
    > EU/USA should enforce a common, secure method for sending text messages to mobiles. No way do we want any regulation here! I will accept balkanization of messaging apps for the lack of government interference here. If a government messaging standard is introduced, it will absolutely be designed to consider lawful intercepts like US CALEA. It would be a key escrow system upon inception. EDIT: downvoters, join the debate. Do you feel differently? If so, why?
    - 8y ago
Spooky23 8y ago
Why isn't the network cleartext then?
- topspin 8y ago
  It is to the network operator. And anyone that has compromised the operator by any imaginable means, including whatever star chamber forces the operator to hand it over.
  - zamadatix 8y ago
    The same is true of any endpoint trust relation, including that of certificates for HTTP/2. That you can't fully trust anyone but yourself isn't an argument for less security.
    - ecnahc515 8y ago
      Certificates allow for decentralized trust, we just rely on a centralized CA. If we didn't trust the central CAs, we could still all run our own CIs and trust individuals. Whether that's actually something anyone would do is different, but technologically, https allows for not trusting anyone but yourself and the organization your speaking to.
    - Spooky23 8y ago
      End of the day, even CA compromise is failure evident in most cases. If you're worried about nation-state actors, the risk is really defects in key negotiation. With mobile standards, the technology is fundamentally such a joke that people come up with wonky technical reasons to avoid talking about the political problems. We probably offer better security for sporting event feeds than we do for critical communications infrastructure.
tfha 8y ago
When I think about lower level security, I think about things like jamming and signal intercepting, and I think about things like being able to tell that you've connected to the right tower. Secuirty at the client and server layer doesn't help you if you can't get connected at all.
Thorrez 8y ago
HTTPS isn't automatically secure. It depends on certificates being issued correctly. But certificate issuance depends on insecure protocols: DNS and BGP. Also there's hijacking account recovery and 2 factor codes via SMS. https://www.theverge.com/2017/9/18/16328172/sms-two-factor-authentication-hack-password-bitcoin https://www.theverge.com/2017/9/18/16328172/sms-two-factor-a...
- ndnxhs 8y ago
  SMS 2fa has long since been considered harmful.
  - Thorrez 8y ago
    Yes, but many sites still use it for 2fa. And regardless of 2fa, it's also commonly used in account recovery which is even worse than 2fa.
jVinc 8y ago
If I don't trust security in the low levels of the stack, why should I trust no security in the low levels of the stack? If I'm not certain of the low levels I can always add security. Why not just have security in the low levels so you completely eliminate insecure communication. Security by default.

lgierth 8y ago

I agree that the security of communication between endpoints mustn't be trusted to the lower layers, but this is only the application layer. The network itself needs to be secured just as well -- thinking especially of SS7 and BGP and the likes here.

dullgiulio 8y ago
Good point. With BGP you can cause a denial of service. But again, TLS should reduce the risk to just that and nothing worse (intercepted/counterfait information.)
- bdamm 8y ago
  This isn't just about preventing denial of service. It's also about preventing direct attacks to your phone's base-band controllers. It's also about reducing the leverage attackers have to manipulate weak applications.
tptacek 8y ago
The error here is in think of security as something you have or don't have. But of course, it doesn't work like that. Security is an economic problem. You deploy countermeasures to raise the cost of an effective attack beyond what rational or realistic attackers will be willing to pay. What does that mean for SS7? It's a little tough to say: you have to peel off all the layers above and below it and factor out the security they provide, and then map what's left to attacks that are meaningful to realistic attackers. All this is to say, the kind of security most people think about when they discuss 5G and SS7 security --- universally trustworthy cryptographic secure channels --- is not a good fit. I tend to think the same thing about BGP (vis a vis global signing schemes like RPKI), but I recognize that I'm an oddball in that regard.
- freedomben 8y ago
  I tend to agree with you, tho when I consider security of the 5G network I think more about large-scale disruptions due to compromise rather than targeting of individuals. Example scenario: War breaks out between two nations (such as the US and China, or US and Russia, or some other country). Cyber attack from enemy shuts down many if not all wireless communication. That would be a catastrophic disaster, and something that does seem like a legitimate defense consideration. That said, I tend to think that free and mutually dependent trade is a good solution here (basically the opposite of Trump's trade war). Going back to the ancients, the countries with the most trade are the least likely to engage in hostile acts. There's an old saying, "where goods cross borders, armies don't."
  - mycall 8y ago
    This is where mesh networking comes into play for LWAN fallback.

peterwwillis 8y ago

> No matter which attacker we want protection against, the points to secure are client and server, not the middle-boxes. > Here we are talking about implementing security in hardware (bad idea: hard to upgrade as security requirements and practices chage) at a very low level (at data link layer). If this is to skip security at higher levels of the stack, you have to trust all hardware vendors and operators worldwide. If we don't, we can as well communicate on an insecure channel: that's what modern TLS provides. So you're turning off WPA on your wireless router, I take it? TLS is not a panacea, and there are many attack vectors for devices and applications throughout the entire network path. Defense in depth suggests security be applied wherever there is a vector.

kstenerud 8y ago
You turn on WPA to stop other people from using your WIFI, and to provide a minimum level of protection for your non-encrypted communications (legacy apps). And, of course, every few years the current wireless protection systems are defeated, rendering the whole thing useless until you upgrade your hardware (because nobody wants to spend money to provide a software fix for something you've already bought).
- zamadatix 8y ago
  The same could be said for TLS, this seems like you're strengthening the argument of defense in depth.
  - kstenerud 8y ago
    Tls is better than nothing, but still not that great. The best would be per app end to end encryption, but that would be a ton of work, and suffer from each implementations mistakes, so you're left with a trade-off between security and doability.
- deleted 8y ago
  [deleted]

gruez 8y ago

By that logic, we shouldn't bother securing wifi APs because everything's encrypted at the application layer anyways. Also, AFAIK SMS and VoLTE don't have additional encryption, so if the data layer is compromised, so are those services.

gcb0 8y ago
well, people do use wifi from hotels and airbnb...
- deleted 8y ago
  [deleted]
- gruez 8y ago
  In that case, having secure/unsecure wifi doesn't really change the equation because the operator itself can still be hostile, even if the link is secure. Having secure (eg. WPA enterprise) wifi only means that some random guy can't intercept your traffic. However, at home, having a secure network is definitely important because of legacy protocols (SMB) or unsecured services (LAN facing http servers)
y0ghur7_xxx 8y ago
> By that logic, we shouldn't bother securing wifi APs because everything's encrypted at the application layer anyways. Sure. Why not? I do banking and I read my email on public, untrusted networks like airport and hotel wifi, Starbucks and the internet. I see not problem with that.
- syn0byte 8y ago
  Public & untrusted != Unencrypted. Otherwise TLS ain't doing shit for you if I control everything you see at layer 2 and up, including the encryption keys and their validity. Would you care to try doing your banking over my WEP-only secured 802.11b network?
  - y0ghur7_xxx 8y ago

noselasd 8y ago

You have to have security at that level as well. The protocol stack services that maintains the radio links to cell towers are client and servers, other parts are between the cell phone and the mobility management node are client and servers. These are services you as a cell phone user don't interact with directly, but still very important as they provide authentication of the user and (ideally and hopefully) authentication of the network, access or indication of your location, and other neccesary services needed to seamless move between cell towers.

move-on-by 8y ago
yup, its called defense-in-depth

okl 8y ago

The author does not care about security, he cares about increasing funding and power of the FCC. > Mr. Wheeler is a former chairman of the Federal Communications Commission.

archgoon 8y ago
One can both be a former chairman of the FCC and care about security. I think you need to expand on your argument to justify your claim. Has the author previously opposed pro security proposals?
- okl 8y ago
  Yes, you are right.

mtgx 8y ago

Still, it would've been nice if the new RCS messaging system would've had end-to-end encryption by default. Or at least that 5G got strong protection against Stingrays. But we all know why none of that happened. The wireless network protocols are designed with the "help" of the world's top intelligence agencies (and no, that's not so we can benefit from the additional security).

BostonEnginerd 8y ago

I disagree with you - security is important at all layers of the stack. Right now, your mobile phone will connect to fake towers (Stingray). This means that SMS 2FA codes can be intercepted to you, I believe. https://nakedsecurity.sophos.com/2018/04/06/washington-dc-awash-with-fake-cell-towers/ https://nakedsecurity.sophos.com/2018/04/06/washington-dc-aw...

silvestrov 8y ago
No, the problem is that the SMS standard was never updated with an encrypted version. Apple didn't want to open iMessage to the world. EU/USA should enforce a common, secure method for sending text messages to mobiles.
- simias 8y ago
  I agree with your main point but I feel like SMS is going to remain cleartext forever. It's basically like email (it's not like encrypted email formats ever gained mainstream traction). Besides I can't really imagine the EU/USA pushing for end-to-end SMS encryption. Fortunately as data plans get cheaper we have plenty of alternatives for encrypted messaging on smartphones.
  - dbdjfjrjvebd 8y ago
    Didn't the UK prevent SMS encryption when the standard was developed?
- wyldfire 8y ago
  > EU/USA should enforce a common, secure method for sending text messages to mobiles. No way do we want any regulation here! I will accept balkanization of messaging apps for the lack of government interference here. If a government messaging standard is introduced, it will absolutely be designed to consider lawful intercepts like US CALEA. It would be a key escrow system upon inception. EDIT: downvoters, join the debate. Do you feel differently? If so, why?
  - 8y ago

Spooky23 8y ago

Why isn't the network cleartext then?

topspin 8y ago
It is to the network operator. And anyone that has compromised the operator by any imaginable means, including whatever star chamber forces the operator to hand it over.
- zamadatix 8y ago
  The same is true of any endpoint trust relation, including that of certificates for HTTP/2. That you can't fully trust anyone but yourself isn't an argument for less security.
  - ecnahc515 8y ago
    Certificates allow for decentralized trust, we just rely on a centralized CA. If we didn't trust the central CAs, we could still all run our own CIs and trust individuals. Whether that's actually something anyone would do is different, but technologically, https allows for not trusting anyone but yourself and the organization your speaking to.
  - Spooky23 8y ago
    End of the day, even CA compromise is failure evident in most cases. If you're worried about nation-state actors, the risk is really defects in key negotiation. With mobile standards, the technology is fundamentally such a joke that people come up with wonky technical reasons to avoid talking about the political problems. We probably offer better security for sporting event feeds than we do for critical communications infrastructure.

tfha 8y ago

When I think about lower level security, I think about things like jamming and signal intercepting, and I think about things like being able to tell that you've connected to the right tower. Secuirty at the client and server layer doesn't help you if you can't get connected at all.

Thorrez 8y ago

HTTPS isn't automatically secure. It depends on certificates being issued correctly. But certificate issuance depends on insecure protocols: DNS and BGP. Also there's hijacking account recovery and 2 factor codes via SMS. https://www.theverge.com/2017/9/18/16328172/sms-two-factor-authentication-hack-password-bitcoin https://www.theverge.com/2017/9/18/16328172/sms-two-factor-a...

ndnxhs 8y ago
SMS 2fa has long since been considered harmful.
- Thorrez 8y ago
  Yes, but many sites still use it for 2fa. And regardless of 2fa, it's also commonly used in account recovery which is even worse than 2fa.

jVinc 8y ago

If I don't trust security in the low levels of the stack, why should I trust no security in the low levels of the stack? If I'm not certain of the low levels I can always add security. Why not just have security in the low levels so you completely eliminate insecure communication. Security by default.