Improve SSL Security from Man-In-The-Middle-Attacks

[DarthGandalf]

Reported by da2ce7 on 17 Mar 2012 02:45:10 UTC In the current version of KVIrc, the program will blindly connect to the same server with a different SSL certificate. (Identified by its Fingerprint).

This is a major security issues, as people connecting to their bounces may get their password stolen, or connecting to IRC servers, have their nick-server passwords/identities/channels taken from them.

KVIrc should follow the standard practice used by SSH:

• [ ] Upon first connection to a server, a warning should be displayed for the user to check the servers SSL fingerprint against a known good source.

(Maybe KVIRC should ship with a list of known good SSL certificate fingerprints, for the popular servers, such as Freenode.org)

• [ ] When connecting to a server and different (non-whitelisted) SSL certificate is provided, KVIrc MUST refuse to connect until the user has whitelisted the SSL certificate.

If KVIrc just displays a warning however connects anyway, the damage is already done, as the malicious attacker already has the passwords, and identification information.

This is a security related bug for KVIrc, and should be fixed in the next public release.

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Migrated from: https://svn.kvirc.de/kvirc/ticket/1274

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Edited Thu 4 Aug 15:08:40 UTC 2016

A shortlist of ESSENTIAL SSL support bits.

• [ ] way to verify the current certificates/block or whitelist
• [ ] way to deny self signed certificates optionally
• [ ] way to monitor which SSL methods / protocols are when using SDCC methods like SDCC file transfer SDCC voice etc.
• [ ] warnings and ssl certificates popups a la mIRC
• [ ] warnings when using low security methods for SDCC
• [ ] more verbose output related to SDCC in transfers window

in short a better way to manage SSL connections and all related tasks

[DarthGandalf]

Comment by ctrlaltca on 18 Mar 2012 19:53:03 The basic kvirc support for ssl is meant to provide communication security, not authentication. If you want to implement authentication, it can be done using scripting: please have a look at [http://www.kvirc.ru/forum/topic,1095.0], ticket #1170, revision r5889 Hardcoding certificate fingerprints inside kvirc is probably a bad idea, due to out slow release cycle. Adding a dynamic certificate datastore to kvirc, some certificate checking facilities and maybe providing some base certificates is probably a nice idea. Or could provide a way to interface with the system certificate datastore.

[DarthGandalf]

Comment by wodim on 05 Apr 2014 13:59:54 This is a complicated matter. Most servers with SSL use a self-signed certificate anyway.

My opinion is that two things can be implemented:

• Check the certificate against the certificate store of the OS (mIRC does this). Some networks such as freenode use reputable certificates that pass validation.
• Check if the certificate has changed since the last connection that was done to that server, à la SSH.

[DarthGandalf]

Modified by HelLViS69 on 02 Jan 2015 14:50:35 Version: 4.0.4 Insomnia → 4.2.0 Equilibrium

[DarthGandalf]

Comment by DarthGandalf on 03 Feb 2015 00:00:02 https://github.com/znc/znc/issues/156 and http://www.cs.utexas.edu/%7Eshmat/shmat_ccs12.pdf for some background and possible solutions.

[un1versal]

+1 for the proposed suggestion above. In fact +1 for upgrading this to higher priority.

[xrogaan]

Yes please :+1:

[un1versal]

There's plenty of ideas, just needs a brave, talented and willing developer who has interest in this with spare time to spare to implement it. That is the only stopper for all these reports ;)

[un1versal]

We have $context.getSSLCertInfo already supported in KVirc http://www.kvirc.net/doc/fnc_context.getsslcertinfo.html so that should help some.

[un1versal]

This is a security related bug for KVIrc, and should be fixed in the next public release.

hahahahaha hilarious 5 years on not even development versions support any better or more robust methods. IMO its terrible, but there we have it

edit removed all the extra labels, I could just wack 50 labels on it, but that wont help devs take any action into this issue

[wodim]

Inspired by ZNC: store the server's fingerprint (this is, the result of $context.getSSLCertInfo(fingerprintContents, remote)) in serverdb.kvc. On connection, if the fingerprint in serverdb.kvc is different from what the server is sending us, ask the user what to do (trust this time/trust always (would store the new fingerprint in serverdb.kvc)/abort).

I wonder though if networks with many servers have different fingerprints for every one of them.