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How to decrypt wireshark captures
How to decrypt wireshark captures













how to decrypt wireshark captures

When the browser is installed it has a relatively small number of public keys (commonly known as certificates) pre-installed. Essentially we sign the data so that if decrypts with the public key people will know the data came from the server. Now weĭo the opposite: We use the private key to encrypt data so that it can only be decrypted with the public key. Previously we used the public key to encrypt data so that only its intended destination could descrypt it. This is where another function of Public Key Cryptography comes in. It will have to retrieve them from the servers and then somehow make sure they belong to the server they are interested in. The client cannot possibly know every single public key - there are millions of them. Is it? There is still one issue in the above scheme! How will the client get the server's public key? More specifically how does it know that it speaks with the server proper, and not some crook who managed to insert themselves in the middle (See Man In The Middle attack)?

how to decrypt wireshark captures

The server uses its private key to retrieve the session symmetric key and all is well. That means that it cannot be extracted from a captured network stream, and since it is used for the rest of the session, neither can any of the information that is transmitted later on. Since the symmetric key is encrypted like this, it can only be decrypted using the server's private key. The client uses the server's public key to encrypt a rather long random key for a symmetric algorithm at the start of each encrypted session. The server has a key pair that consists of a world-readable public key and a securely stored (and inaccessible to anyone but the server itself) private key. The public key is widely accessible to "everyone" while the private key is stored securely and only used by its owner. Assuming a sufficiently strong algorithm, whatever is encrypted with the public key can only be encrypted with the private one and vice versa. Those involve two keys, rather than one, a public key and a private key. Public Key Cryptography is based on asymmetric encryption algorithms. I will add some more information in layman terms, mostly ripped off from the two links above, to make things a bit more clear. See also the Wikipedia article on TLS for more information. You would need the private keys of the server in order to descrypt an SSL session and in normal situations it is quite hard to acquire those. Said public keys are accessible, but they cannot be used to decrypt the session packets because the encryption algorithm is not symmetric. What you have in your browser key-store is the certificates that will verify the validity of the public keys of the server. That is the whole point of Public Key Cryptography on which SSL is based. No, you cannot decrypt HTTPS/SSL sessions from a network capture, even if you do have the certificates.















How to decrypt wireshark captures