56

Some background: Wireshark supports decryption of SSL sessions when the master secret can be calculated (which can be derived from a pre-master secret). For cipher suites using the RSA key exchange, the private RSA key can be used to decrypt the encrypted pre-master secret. For ephemeral Diffie-Hellman (DHE) cipher suites, the RSA private key is only used ...


48

It appears to be a feature called Spotify Connect. Spotify allows you to play music from you phone or computer using your Roku or smart TV, as most people will likely have better sound systems for their TVs than for their computer. Presumably your Spotify desktop app is automatically scanning your LAN and querying compatible devices to be able to offer this ...


45

With HTTPS the path and query string of the URL is encrypted, while the hostname is visible inside the SSL handshake as plain text if the client uses Server Name Indication (SNI). All modern clients use SNI because this is the only way to have different hosts with their own certificates behind the same IP address. The rest of the URL (i.e. everything but ...


29

This is because in an SSL/TLS connection the asymmetric key exchange uses the server's public key to exchange the pre-master secret. A client certificate is only used for client authentication if the server requests it. The pre-master secret is what's used to generate the session keys. This is why you need the server's private key, not the client's. ...


21

Both are same kind of attacks. The difference is Eavesdropping could be in any form (Physical to logical), where the sniffing is more electronics/network related term.


18

Note: as of OpenSSL 1.1.1 (unreleased), it will be possible to set a callback function that receives the key log lines. See the SSL_CTX_set_keylog_callback(3) manual for details. This can be injected as usual using a debugger or a LD_PRELOAD hook. Read on if you are stuck with an older OpenSSL version. For a walkthrough of the LD_PRELOAD approach for Apache ...


18

I presume you pulled this from the "capture HTTP GET requests" filter example. First, some notation: var[n] means the nth byte of var. var[n,c] means c bytes of var starting at offset n, e.g. var[3:4] would return bytes 3,4,5,6 of var. & is the bitwise AND operation. >> means bitwise shift right. So, what do we have? tcp[((tcp[12:1] & 0xf0) ...


15

The keylogger looks to be sending email using Gmail but the SMTP communication is encrypted with TLS (SSL). Simple Mail Transfer Protocol Command Line: STARTTLS\r\n Command: STAR Request parameter: TLS Simple Mail Transfer Protocol Response: 220 2.0.0 Ready to start TLS\r\n Response code: <domain> Service ready (220) ...


14

Wireshark is a very powerful tool. In most cases, the (addon-less) debug consoles of the browsers firefox and chrome should be enough. Both have network monitors that are sufficient most time. Be aware that the firefox' monitor doesn't support websockets yet. If you still wanted to use wireshark, then consider utilizing the SSLKEYLOGFILE file, more help at ...


13

With new versions of wireshark: Make sure the traffic is decoded as SSL, i.e. setup the SSL analyzer for this TCP stream in Analyze >> Decode As. Now it will show the SSL details for the packets. Pick the packet which contains the certificate, in this case packet 6. In the packet details expand Secure Socket Layer etc until you get to the certificate ...


12

(Adding a new answer which should be definitive, leaving the old around as it's useful debug for how we got here. Credit for pointing to the actual answer in comments goes to @P4cK3tHuNt3R and @dave_thompson_085) Using Wireshark, I am trying to determine the version of SSL/TLS that is being used with the encryption of data between a client workstation ...


11

The thing about passive sniffing is that you don't get other people's network traffic unless you're either in a position to see that traffic due to network topology (e.g. you're sniffing a trunk port) or are doing network spoofing (e.g. ARP spoofing) that causes packets to be sent to your device. If they're doing the latter, you just need to look out for ...


11

The private key is private to the webserver. If you don't control the webserver you shouldn't be able to obtain it. The certificate only holds the public key so it wouldn't be of much use to you. You could try to setup a proxy https server and do a man-in-the-middle attack - in that case you would have the key of your proxy server. Are you trying to crack ...


11

You want to look at the "protocol version" in the ServerHello message. Consider this image, shamelessly plundered from the Web and that shows a screenshot of a ServerHello being decoded by Wireshark: There are two "Version: TLS 1.0 (0x0301)" instances in this picture. The first one is from the header of the record that contains the ServerHello. The second ...


10

Both HTTP headers (containing requested URL) and application data in HTTPS is encrypted. You can see requested hostname, because browsers send it in Service Name Indication extension during handshake, so that server can choose matching SSL certificate.


10

PART 1: Generic explanation, unnecessary to read if you have read the question. The first (how does the packet arrive at the attacker): Victim sends a packet with source IP '192.168.1.3' and source MAC '00:00:00:00:00:03' to destination IP 'DEST' and destination MAC '00:00:00:00:00:01'. Where 'DEST' is some external IP like '47.32.1.6' The router ...


10

Wireshark captures all traffic on a network interface. The thing with HTTPS is that it is application layer encryption. Wireshark is not able to decrypt the content of HTTPS. This is because HTTPS encrypts point to point between applications. The idea here is that HTTPS traffic that travels over the Internet is confidential, a random router or person who ...


9

There's two ways to decrypt SSL traffic in-transit: The first is to have the private key of the server. If you have that, you can feed it to wireshark which will do the rest. There are a handful of dedicated tools for this as well. But it can't be done without the server's private key. The second is to MITM the connection. Fiddler will do this, as ...


9

If you can "expose the premaster secret", though the key exchange uses ephemeral Diffie-Hellman, then you have privileged access to either the client or the server. That's one of the points of DHE: the actual key exchange uses newly generated DH key pairs, which neither client or server stores anywhere except in its own RAM. Having a copy of the permanent ...


9

Using wireshark, you will be able to find out the host name, as mentioned by some other answers, due to SNI. Also, you'll be able to see some parts of certificates. The https URLs you've seen were probably the URLs of CRLs or OCSPs. If someone could get at your URLs by walking your site, and compare the size of the returned pages with the size of what's ...


9

As you guessed, Facebook uses HTTPS, what that means is that requests to Facebook.com regardless of whether they are GET or POST requests are not sent over HTTP, instead they are sent over HTTPS in an encrypted form which the 'http' filter in Wireshark wont be able to display as regular HTTP requests. If you want to view the encrypted HTTPS traffic including ...


8

You can't, unless you have administrative control over the 3rd party web server, or retrieve the certificate via some other nefarious means. SSL/TLS is reliant upon the private certificate staying private. Furthermore, even if you had the server's private key, you might not be able to decrypt traffic from an earlier session if Perfect Forward Secrecy was ...


8

You should probably start with a general overview of how TLS works. We have a good introductory post here: How does SSL/TLS work? To answer your question: every time a new TLS connection is opened, you will see something like this message exchange in Wireshark: The Hello and Key Exchange messages are to set up an encrypted channel that only the client and ...


7

Network traffic can be either unicast or broadcast (or multicast, but that's not relevant right now.) NBNS (NetBIOS Name Service) is broadcast, so the switch (your wireless "router" in this case) has a responsibility to deliver it to every host "attached" to it. Most other traffic is unicast, which means the switch should send it directly to the recipient. ...


7

In "Promiscous mode", the driver still outputs standard ethernet frames belonging to the one wireless network you are currently associated to (identified by the BSSID). Possibly the device will only dump packets from the AP to wireless devices, but not packets from wireless clients to the AP, as receiving packets from non-AP devices is not used in AP client ...


7

The ".PEM format" does not really exist as a standard. This is more "whatever OpenSSL does". PEM comes from an old failed standard for Privacy Enhanced Mail (that's what the acronym means). These days, "PEM" really means: some text that looks like: -----BEGIN XXX----- [some Base64 stuff here] -----END XXX----- I.e. a header line that starts with ----- and ...


7

The NSS SSL Keylog file is a non-obtrusive way to extract SSL session keys from an application using the NSS library for SSL/TLS, but there is no standard way to do the same in all applications. (A generic approach would involve a man in the middle attack, but this is not really non-obtrusive.) The idea of the extracting session keys directly from the ...


7

The (Pre-)Master-Secret is unique per TLS session. If you want a third party to be able to decrypt a specific pcap with this TLS session but not anything else it is safe to give the party this secret, as long as the session is not reused anywhere else. Note that a TLS session can span multiple TCP connections. To make sure that the session will not be ...


6

If by remote you mean "on my local LAN but not me" then the answer is possibly; If by remote you mean "on a remote LAN" then the answer is "No, not with Wireshark." You'd be looking for something like a network probe with RMON capabilities. You could use a Span or Mirrored port as Lucas points out or you could force the switch to begin forwarding packets ...


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