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20

There are many VoIP services that provide ID-spoofing functionality Jumblo: Create an account and add some credit to it (10 Euros minimum excluding VAT), then install their Android app, login, the go to Settings and choose "Add Caller ID" then add the number. (Requires SMS verification) * Skype: You can create an online number (15 Euros minimum) then add ...


16

Browsing through the source on GitHub, one learns that it uses ZRTP. From What are the vulnerabilities of VOIP-specific security protocols? : Prateek Gupta, Vitaly Shmatikov (2006) Security Analysis of Voice-over-IP Protocols We also demonstrate a man-in-the-middle attack on ZRTP which disables authentication and allows the attacker to ...


12

In general yes, there is ways of doing this, as a quick google search would've been able to tell you. When ever you call, write or send a file to a person on skype you make direct contact with the persons IP/ISP IP, and that you are of course able to track. A simple way to do it in windows is using netstat -n while in a call, and look for the port you know ...


12

Mumble's home page states it uses public-key cryptography. This is done by using the TLS protocol, which is mentioned in the FAQ. With public-key cryptography, the private key is always known by the server. Thus, a Mumble server administrator indeed has access to the private key - usually in the form of a X.509 certificate - which can be used to decrypt the ...


9

In the Skype protocol there are also "proxy nodes" that relay traffic for you. Every Skype client can in fact become such a proxy node if the network reachability is good, especially in regard to firewall conditions. So you can't be sure if the peer IP address you are seeing is the one of your call partner or of a random proxy node. In the latter case you ...


9

I'll have disagree with AJ's answer. When making a RedPhone call you're first authenticated by one the authentication servers and then a relay server handles connecting you to the call recipient. All of these communications are encrypted. Since the caller isn't directly connected to the recipient (most you need NAT traversal on mobile data networks) , your ...


9

When the call is coming from an external PBX, then the Caller ID you receive is what the caller's service provider sends to your service provider. This could by anything the caller's service provider wants. Many service providers choose to respect that and send the real Caller ID to your service provider (and eventually, to you). Many SIP / VOIP service ...


8

The STIR IETF charter group is working on this problem now. (Literally right now, join the Jabber or listen) Namely this article highlights the need for CallerID due to Robocalling Phishing DoS attacks Former solutions include: RFC 4474 defines SIP "Identity", however this isn't compatible with existing deployments so it hasn't been used. RFC447bis ...


8

Caller ID is always insecure, VOIP Caller ID is no more insecure than any other. If you want to know for sure who the caller is, you have to do a trace rather than trust the included information. Caller ID is kind of like politely asking someone for their name, they don't have to tell you the truth.


7

Payload encryption means they can't know what the communication content is, but in some cases they can still know what protocol you're using (In this case Skype). This is how countries block Tor, for example. Methods to detect the protocol being used even if it's encrypted: IP-based: TCP is not encrypted even if the payload is encrypted (So that computers ...


5

Redphone is not designed to prevent meta-information capture. It still is possible for someone monitoring to figure out who you are talking to and how long you talked since no onion routing or similar system is implemented by it. However, it should protect the security of the contents of your communication since the encryption keys are unknown by anyone ...


5

Putting findings in an answer instead of comments seems to be the best approach. As usual, turns out this has been discussed before. A quick search on CiteSeerX gave 50 papers, however not quite up-to-date: Angelos D. Keromytis (2009) Voice over IP: Risks, Threats and Vulnerabilities Prateek Gupta, Vitaly Shmatikov (2006) Security Analysis of Voice-over-IP ...


5

When you do a call from SIP to a regular phone line, somewhere in the middle it will exist a gateway which translates the phone call from IP network to a PSTN. So it is doable someone in the middle intercept the communication (in the IP network or PSTN), at least, to lawful interception. Only if two SIP peers call directly is less possible the have a ...


5

The simple answer is that this is not considered a vulnerability - the protocol stack is not designed to authenticate the caller. From @schroeder's Wikipedia link on Caller ID: Additionally, nothing ensures that the number sent by a switch is the actual number where the call originated; the telephone switch initiating the call may send any digit string ...


5

There is something between the scanner and the target that is responding on behalf of the target, spoofing its source address so as to appear to be the target itself. When you ran the Nmap scan as root with --reason -v, it showed the IP Time-to-Live (TTL) values of the response packets for each port: PORT STATE SERVICE REASON 21/tcp open ftp ...


4

Considering every VOIP phone is different, it's kind of hard to standardize depending on where the storage module is located. There are companies who are specialized in hardware destruction, opting for performing destruction yourself can be very very tricky. Should you be able to locate the storage module you could use the Guidelines for Media Sanitization ...


4

A TeamSpeak identity is simply an ECC key pair for the NIST curve ECC-256 as generated by the libtomcrypt library, together with a counter value that is a 64-bit unsigned integer. The security level makes use of a classical Proof-of-work system. Let PUBLICKEY be the base64-encoded string of the identity's ASN.1 DER encoded public key. Further, let COUNTER ...


4

Skype apparently had some known vulnerabilities, but most are old: http://www.cvedetails.com/product/18729/Skype-Skype.html?vendor_id=8920 https://www.cvedetails.com/vulnerability-list/vendor_id-2302/product_id-4023/Skype-Technologies-Skype.html You might also be interested in reading Skype's security page http://www.skype.com/en/security/ Without going ...


4

Whatsapp uses specific ports including: 5223, 5228, 4244, 5242, 5222. By monitoring packets to these ports, it is very easy for a packet filter to figure out which clients are trying to conduct a Whatsapp session. The problem is made easier because Whatsapp uses TCP, a sequential protocol. Using this protocol makes it even easier to target and interrupt. If ...


3

The method that is used is based on hashcash. http://en.wikipedia.org/wiki/Hashcash Hashcash is a proof-of-work system designed to limit email spam and denial-of-service attacks. Source: http://forum.teamspeak.com/showthread.php/57988-Security-level-how-is-it-determined-increased-technical?p=257115#post257115


3

I couldn't find any articles stating this and I highly doubt they would charge you for it (unless you are using their VOIP services instead of skype). The reason for this is that some providers prioritize this type of traffic on their network and some even have special separated networks (this only works for their VOIP phones/services). You can't really ...


3

Ethereal was renamed Wireshark back in 2006 due to trademark issues. Ethereal/Wireshark is just a packet capture tool with a GUI front end, there are many packet capture tools available. As to intercepting particular traffic, that would depend on particular network architecture and/or various attack methods that end up being a man in the middle.


3

If you can directly connect, you can tunnel just about anything over SSL using stunnel. Any other sort of port-forwarding arrangement would also work. If you're using something more complicated involving SIP, you'll have to build a custom application or a fancier proxy that works in tandem with directory services. I haven't used this in forever, nor has it ...


3

I think there are many factors that could make it a legitimate request: other people in the home who might need network segregation load balancing old equipment (getting a newer modem) VPN configurations I, myself, have made the same request to a certain remote employee to ensure separation of use within that employee's home. Sometimes it's simply to ...


2

I think both posters are correct. Skype will or will not make a direct connection. For example, if you are sitting next to each other with a friend, go online in Skype and transmit a file between both of you. You should notice amazingly fast transmission speed, as Skype detects that you are located on the same network and therefore it makes a P2P connection. ...


2

A secured phone line would indicate that there is encryption in place. This would be similar to how we do encryption in networks using TLS, etc. The line on it's own would not typically be encrypted, but the data flowing over the line would be encrypted. Typically, there is encoding software/hardware built into the phone units or you could encrypt the data ...


2

Vomit was an old one I think Cain and Able has this functionality as well.


2

This option basically allows registered hosts to call without re-authenticating. According to this article: Never include the parameter “insecure=invite” or “insecure=very” when defining a dynamic SIP user account. If you do, it will disable password checking for that account. Where possible, restrict the range of IP addresses from which the user ...


2

NIST has created SP 800-164, "Guidelines on Hardware-Rooted Security in Mobile Devices". It is a document that discusses not only the destruction of the device, but other security features that you should be considering, including remote wipe, certificate management, device integrity, using isolation to address various threats, key storage, BYOD, etc. ...


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