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1 vote

P-384 vs. SHA384

These are two different ciphersuites. With regard to ECDHE_RSA_WITH_AES_256_GCM_SHA384 - the SHA384 component is the hashing algorithm used to ensure data integrity during the TLS handshake With ...
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  • 19.3k
-1 votes

For organizations running modern, functioning PKI, can mTLS be used as SSO mechanism?

Mutual TLS connections provide an "AlwaysON" proof of possession. Malicious software can inject data silently if the software has already opened the private key. Two factors as Yubico or ...
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1 vote

REST API behind proxy, is TLS sufficient?

I think that the only missing part is the traffic between your nginx and your backends. In general, this is handling by using your own certificates and mTLS, so you have your connections from users/...
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  • 1,932
5 votes

Is it safe to ignore/override TLS warnings if user doesn't enter passwords or other data?

There are, to my knowledge, 2 risks of connecting to a site without TLS, both of which have been mentioned in some ways, but I wanted to give my own spin on them: Safety. The potential for man-in-...
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  • 151
0 votes

Validate HTTPS traffic at later time

TLSv1.3 explicitly prevents this kind of traffic analysis "at later time", i.e. without having the internal state of both sides. This is called "perfect forward secrecy" (PFS). In ...
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  • 3,395
8 votes

Is it safe to ignore/override TLS warnings if user doesn't enter passwords or other data?

It depends on the stakes involved. The broken TLS will not, by itself, damage the browser, the downloading computer and the file. If the file is "look how funny my dog jumps" video and the ...
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  • 3,395
29 votes
Accepted

Is it safe to ignore/override TLS warnings if user doesn't enter passwords or other data?

Of course the site should upgrade its TLS setup. But, until the site owner does that, the user that needs to download the file from the site must look for a workaround. The user can proceed to ...
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  • 19.3k
0 votes

X509 / SSL certificates in practise

You're not really asking about X.509 and certificates, but how they are used within the TLS handshake to arrive at a secure and authenticated AES session key. I would recommend you study this page, ...
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10 votes

Is it safe to ignore/override TLS warnings if user doesn't enter passwords or other data?

You need TLS, no excuses. Even if the user isn't sending anything confidential to the site, they are downloading from it. Any attacker in the position to perform a MitM attack will be able to change ...
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  • 50.5k
9 votes

Is it safe to ignore/override TLS warnings if user doesn't enter passwords or other data?

Yes, you need TLS for read only websites. Because otherwise a rogue WiFi hotspot can serve whatever content it wants on your domain and the user has no way to know it's not authentic. Also, browsers ...
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  • 7,603
1 vote
Accepted

Email TLS coverage for forwarded recipient email address

Email encryption is almost always* per-hop, between client to server or server to server. You can review the Received headers to see whether encryption was used on a given hop: Received: from ...
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  • 71.3k
3 votes

Secure FTP (AUTH TLS) fails from office lan

FTP is an old protocol and is not really firewall friendly. It requires one connection from a random port (on client) to port 21 on server for the command channel and a connection between a random ...
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2 votes
Accepted

Is providing a static TLS key during an OpenVPN handshake useless for commercial providers?

I don't think it's useless. Think of pre-shared key as an extra layer of protection for the TLS channel, requiring that incoming connections are correctly HMAC signed by the PSK key. This feature ...
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1 vote

iOS traffic not shown in proxy when SSL pinning enabled

Aside from automatic passthrough (used for connections where Burp's certs are rejected, check Burp's logs), the other possibility is just that the app is no longer using the system-wide proxy settings ...
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  • 38.7k
0 votes

If your router gets hacked, can the hacker acquire your RSA private key to decrypt HTTPS and view full URL's?

You don't need RSA key pair on your side to securely communicate via HTTPS. Browser agrees with the server about keys for the current session. See details here. At one of steps the server sends to the ...
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  • 7,916
0 votes

If your router gets hacked, can the hacker acquire your RSA private key to decrypt HTTPS and view full URL's?

Note that in an https connection, the client does not have a private key - only the server does. Having said that, there are many ways that an adversary can view and/or modify your network connection. ...
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  • 19.3k
3 votes

If your router gets hacked, can the hacker acquire your RSA private key to decrypt HTTPS and view full URL's?

So if your router gets hacked is decryption of https possible and can the complete url of sites that you visit be viewed? In order to decrypt HTTPS one must first be some man in the middle to get ...
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0 votes

If your router gets hacked, can the hacker acquire your RSA private key to decrypt HTTPS and view full URL's?

A hacker cannot decrypt your TLS traffic by hacking your router. The key is generated by the server on the TLS transaction, and it will never be transmitted anywhere. I read that they use packet ...
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  • 50.5k
3 votes
Accepted

Certificate warnings on websites with client certificate authentication

I think that you have a misconception here: using your own CA for client certificates does not imply that you have to use your own CA for the server certificate too. It is perfectly fine to use a ...
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2 votes
Accepted

Java support for TLS_DHE_RSA_WITH_AES_128_CCM

Dave and Bruno have provided the main solution for the issue. These are the steps I did to solve my issue: Downloaded and added files bcprov-$version.jar and bctls-$version.jar to %JAVA_HOME%\lib\ext ...
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-1 votes

Decrypt TLS 1.2 traffic between .NET Windows applications

It is relativly simple to decrypt TLS/SSL traffic using Fiddler from Telerik. It works for any app running on Windows. Here are steps: Download Fiddler from https://www.telerik.com/download/fiddler . ...
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4 votes

Which cipher is more secure TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA or TLS_RSA_WITH_AES_256_GCM_SHA384?

Neither cipher suite is good. Which one is the least bad depends on your threat model. TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA has two problems: It uses SHA-1 to authenticate the server's signature. SHA-1 ...
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1 vote

Which cipher is more secure TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA or TLS_RSA_WITH_AES_256_GCM_SHA384?

Risks of CBC ciphers To attack an implementation vulnerable to variants of POODLE and Lucky13, one of the sides needs to be vulnerable (not a given, e.g. if SChannel is used on both sides it should be ...
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  • 7,603
1 vote

Which cipher is more secure TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA or TLS_RSA_WITH_AES_256_GCM_SHA384?

On the cmd line, try: $ openssl ciphers | tr ':' '\n' This would give you the list of ciphers in the decreasing order of "strength". This list should help you evaluate the two ciphers in ...
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  • 1,136
3 votes

Which cipher is more secure TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA or TLS_RSA_WITH_AES_256_GCM_SHA384?

I agree with @schroeder, I don't think you can do a direct "which is better?" comparison with cipher suites. That said, Mozilla's TLS Recommendations currently lists DHE-RSA-AES256-GCM-...
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4 votes

Java support for TLS_DHE_RSA_WITH_AES_128_CCM

This is very dependent on the version on the JRE that you are using, and thus on the version of JSSE it ships. It also depends on your local configuration, notably the jdk.tls.client.cipherSuites and ...
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  • 4,226
0 votes

Can I concatenate multiple x509 certificates?

I think it's unsupported for cert that may be sent within the TLS handshake, and when I execute openssl x509 -in combined.crt -noout -text, only then first CERTIFICATE block display. But if you ...
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2 votes

Does accessing a server over HTTP vs HTTPS make any difference when using a VPN?

Fun idioms I don't know aside, attack vectors: Attacker inside network being VPNed to pretends to be the HTTP service. Without the Authentication part of HTTPS the user wouldn't know better. ...
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6 votes

Does accessing a server over HTTP vs HTTPS make any difference when using a VPN?

Yes, there is security in adding a layer of TLS to VPN accessible services. The VPN will allow access to the network. It will not secure communications to the services on that network. Credentials ...
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  • 12.2k
3 votes

Why is Nessus report HTTP running a web server on port 80 when I'm sure that it isn't?

TL;DR Security scans often require human evaluation to rule out false positives and false negatives. You also have to read the actual definitions of your tool's results to understand what's being said,...
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3 votes
Accepted

Creating secure website-based login for a desktop app

Rule #1: don't roll your own. It sounds like you are inventing your own version of the SAML or OIDC federated login protocols. I would suggest that you look into those and see if they fit rather than ...
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1 vote

How to perform MitM against SSL/TLS when certificate owned?

This could either be decrypted on the fly, or saved so I can decrypt it at a later date, either approach is fine. You're gonna have to go with decrypted on the fly. The certificate + private key is ...
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0 votes
Accepted

What is the security impact to using a port different from 443 for HTTPS in my router

There have been various attacks in this past (such as this one from 2014 that modified the DNS servers on SOHO routers to malicious ones, and used that to target the users. The attacks essentially ...
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  • 3,571
0 votes

How is man-in-the-middle attack prevented in TLS?

If the attacker can only capture packets, it's not a MitM attack but simply eavesdropping. And in this case, in modern TLS with ephemeral keys (DHE, Ephemeral Diffie-Hellman, or ECDHE suites) the ...
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  • 4,226
0 votes

Internal SSL Certificates?

I've been using xca to maintain an internal Certificate Authority & generate server & client TLS certificates. This guide for xca was helpful With xca it is simple to set additional x509 ...
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