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0 pointsnthm9y ago0 comments

Could you explain how [3] is an RCI bug? getNum() returns either 'false' or 'n' with the length of gibberText (ie. n20, n35, etc). I can't imagine any content where .length() would return harmful code; though I'm not well versed in JS.

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libertymcateer9y ago

I'm also interested to know.

Believe it or not, I would love to get Nik as a consultant. I fear my 'hubris' (I won't deny it, this idea is extraordinarily ambitious and I have to be arrogant to even conceive of it) will have pissed him off irrevocably.

That aside, I don't really follow his point on the login PW. I understand 8 char alphanum pw is pretty low entropy... but that isn't used for encryption. And the login attempt rate is pretty strictly rate limited.

And yes, I am getting professionals - not me - to do the heavy lifting. I wrote the proof of concept. I am in no way surprised to find it has issues - I am aware of a few others myself.

nikcub9y ago

It isn't the login password but the message password - although using sha256 for a login password isn't great either

if you're doing

aes(plaintext, sha2(password)) = cyphertext

given cyphertext I can get to plaintext with sha2(8-char dictionary)

well designed systems will generate a truly random key there, exchanged using public-key. if you're going to use a password, you need a key-derivation algorithm

this is all bunk tho since the big vulnerability here is that you're delivering the encryption routines via javascript in a global browser space

libertymcateer9y ago

> this is all bunk tho since the big vulnerability here is that you're delivering the encryption routines via javascript in a global browser space

So what about mailvelope?

1 more reply

nikcub9y ago

That image isn't very useful on its own.

the design of the app is that it injects content scripts with global variable names everywhere.

any site can overwrite the encryption functions, or redefine some of the global vars that are used for images, etc.

j / k navigate · click thread line to collapse

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libertymcateer9y ago

I'm also interested to know.

And yes, I am getting professionals - not me - to do the heavy lifting. I wrote the proof of concept. I am in no way surprised to find it has issues - I am aware of a few others myself.

nikcub9y ago

It isn't the login password but the message password - although using sha256 for a login password isn't great either

if you're doing

aes(plaintext, sha2(password)) = cyphertext

given cyphertext I can get to plaintext with sha2(8-char dictionary)

well designed systems will generate a truly random key there, exchanged using public-key. if you're going to use a password, you need a key-derivation algorithm

this is all bunk tho since the big vulnerability here is that you're delivering the encryption routines via javascript in a global browser space

libertymcateer9y ago

> this is all bunk tho since the big vulnerability here is that you're delivering the encryption routines via javascript in a global browser space

So what about mailvelope?

1 more reply

nikcub9y ago

That image isn't very useful on its own.

the design of the app is that it injects content scripts with global variable names everywhere.

any site can overwrite the encryption functions, or redefine some of the global vars that are used for images, etc.

j / k navigate · click thread line to collapse