По поводу лайта - комент с офф сайта от разработчиков:
I talked with Bitcoin devs about the openssl CVE-2014-0160 vulnerability that became public on April 7th, 2014. It is believed that Bitcoin 0.9.0 official binaries from bitcoin.org is exposed only with the payment protocol and RPC SSL. Bitcoin 0.8.x is exposed only with RPC SSL.
If the above is true, you are not vulnerable with Litecoin-Qt or litecoind 0.8.x under these circumstances:
You do not use RPC SSL as a client or server. This is not enabled by default, and very few people use this.
If you built from source then you are probably dynamic linking to your system's openssl. So if your system openssl is fixed for CVE-2014-0160 then you are likely fine.
Furthermore in #bitcoin-dev Tuesday, the Bitcoin Core developers talked about trying to reproduce an attack on Bitcoin RPC SSL that tries to extract secrets from memory. In their attempts they were unable to extract anything different from a single 64KB chunk of memory that contained nothing important. It is possible they missed something, but given that this feature is used by almost nobody the risk to Litecoin 0.8.x seems to be negligible.
There is a lot of bad advice out there about emptying your old addresses. Doing so is harmless, but if the above analysis by the Bitcoin Developers is correct it is also useless.
https://litecointalk.org/index.php?topic=17974.0Please help to test the next version of Litecoin to better validate a long list of bug fixes from the previous release. We have no reason to rush this release. We want to be sure no errors are made.
Краткая суть в том, что лайтовый кошелек не использует RPC SSL.