Existing TLS connections can be reused without checking remote hostname
Currently, PJSIP transport can be reused if they have the same IP address + port + protocol. However, this is insufficient for secure transport since it lacks remote hostname authentication.
Suppose we have created a TLS connection to
sip.foo.com, which has an IP address
184.108.40.206. If we want to create a TLS connection to another hostname, say
sip.bar.com, which has the same IP address, then it will reuse that existing connection, even though
220.127.116.11 does not have certificate to authenticate as
The vulnerability allows for an insecure interaction without user awareness.
It affects users who need access to connections to different destinations that translate to the same address, and allows man-in-the-middle attack if attacker can route a connection to another destination such as in the case of DNS spoofing.
Guard against DNS spoofing.
For more information
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- lauriva Lauri Vänskä