Session initiation protocol (SIP) has significantly made communication better over VoIP. It is now possible to start, maintain and end real-time calls whether voice or video calls. The signalling protocol is also useful in messaging applications as well as other communication modes applied in internet telephony.

Success achieved by SIP in enhancing connectivity is enormous. But, security concerns remain a challenge in the implementation of SIP. Attempts have been made to secure exchange of information by use of data encryption, and more are underway. Furthermore, secure tunnelling and IPsec are in place to ensure security in the use of SIP in VoIP. To ensure security for your SMB consider Power Consulting’s cyber security consulting services.

SIP security situation

For a long time telephony environment was secure until recently when malice started infiltrating. To keep communication safe has prompted many service providers to embrace IP connections. SIP integrates the use of both HTTP and SMTP thus a robust security detail must start from securing the two in more information. As with any other technology, challenges are accompanying the use of SIP and the most notable concerns security. Fraud cases were on the decline until the roll-out of IP communication, and this is a great dilemma that needs immediate fixing.

SIP is more evident with VoIP and involves two components; the service provider, and the network element. The two get implicated in SIP security along with intermediaries and external factors. We discuss some of the SIP security issues

SIP Security Issues

SIP-enabled devices are increasingly used globally in conjunction with VoIP applications. Cyber-crime is watering down the success anticipated with the introduction of SIP in telephony. SIP is no longer safe, and there is a need to seek on processes to safeguard the connectivity swiftly. National computer security survey recorded over 63% cyber-attacks in the US. SIP devices are not spared either by these malware challenges. Some take the form of ransomware giving false identity while others target emails. Controlling such anomalies, to ensure safe communication has been marred with very many issues.

SIP has the same security issues like other VoIP. But, certain factors make SIP less secure compared to other IP. These factors include the complexity of the system, encoding, and low maturity levels.

Registration hijacking

An attacker can use valid credentials that one used in registration and replace with their addresses. After completion of registration, all incoming calls will get directed to the new address which is not legitimate. This way, relevant information may end up getting to the wrong person. Weak authentication procedure usually a username and a password can provide a loophole for registration hijacking. The dictionary-style attack gets used by perpetrators to access your SIP-based VoIP during the registration process. Registration hijacking will lead to loss of control of calls. Besides, the hacker can collect sensitive data from your signalling and cause harm to your organization.

A man-in-the-middle attack is also possible following registration hijacking. Here, the corrupt UA has access to calls, change the message then channel the distorted signal to the legitimate owner. Rival firms can use this to frustrate your success and steal your trade secrets.

Impersonation of a server

Also referred to as proxy impersonation, this occurs through a false presentation by an attacker. An attacker may poise as the original server and dupe you to communicate and give critical information without knowing. Through proxy impersonation, one can gain access to SIP messages and calls. The attacker positions between the server/proxy and the users thereby intercepting all communications in this line.

The UDP communication between proxies and be a susceptibility point for attacks. A third party can infiltrate into the connection using DNS spoofing and ARP cache spoofing. These will permit the attacker to manipulate, block and record all outgoing calls from a given UA. This kind of vulnerabilities makes SIP use of being contentious as no safety is assured.

Session tear down

In SIP telephony, BYE messages are sent to signal the end of a call. Attackers can manipulate this and wrongfully send BYE messages before completion of a call thus halting communication. After capturing some initial notes of the conversation, an attacker can draft a signal appearing as originating from one of the participants to terminate connection in the SIP.
If the intruder is acquainted with addresses of the participants the BYE message resulting in session tear down, moreover, one sending excessive BYE messages to firewalls will close all the UDP ports opened in the particular session.

Message tampering

Message tampering aims to alter the content of the message or change the delivery time of a given signal. It can occur through registration hijacking or impersonation. Wrong information is delivered to the receiver thus causing conflict and frustrating the efforts of an organization. Message tampering is made possible because SIP messages have no natural method of ensuring the integrity of data. Message tampering goes along with eavesdropping and packet dropping can get prevented by initiating mechanisms to protect the integrity of data.

Denial of service (DoS)

DoS refers to a form of cyber-attack where the attackers make a call or message services unavailable. Mostly, this is achieved by disrupting connection to the internet. This form of attack can target various components of SIP connection including registrar, proxy, and FW/NAT. DoS attacks are particularly dangerous when focused on voice resources. They can be used to generate excellent information and disturb the intended communication process. It is possible to direct this attack at firewalls, and such an attack will impair proper management of legitimate calls by firewall services. A crowd of purported clients creates congestion limiting the authorized user from accessing the SIP services.

Firewall/Network Address Translation issues

Firewalls are designed to protect users from other network factors that may disrupt connection. However, firewalls can also create a security challenge in some instances, especially for SIPs that use separate IP ports. Such can slow connectivity. This SIP security issue can be taken care of creating an embedded SIP-optimized firewall.

Solving SIP security issues

Integral to SIP security are the building components; IP and VoIP. Controlling SIP security issues using VoIP security recommendations is possible.