kohlrak: Many still prefer 25 for email. I see it open all the time, actually, and more often open than closed.
sanscript: What I meant was blocking telnetting anonymously to p25 (SMTP-MTA), used for server-to-server to initiate the transfer. Client fetching of mail happens over p587 (SMTP-MSA), some still uses p465 with a wrapper of some sort and are basically deprecated according to iana.
Most of the major ones with competent admins had those closed pretty fast (back then), and today it's pretty much idiotic to still allow anonymous access.
Well, you can make a hack to tunnel anything you want in/out of any port you want, but that still depends on A and B to communicate on the same level.
EDIT: The fact that you don't use tls it's pretty easy for others to snoop up your mail-address and passwords, which again is just one of many methods to gather potential targets...
While other accounts exist, i'm the only actual user for the email. Passwords have to be accessed via squirrelmail, as SMTP is only email in, email out. No logging in to do. You have to either use mail or squirrelmail to send emails, so they'd have to brute force that to get anything (to be fair, i don't really have any special protection for it, outside of the crappy hardware). TLS just offers an extra pain (probably not much, but i haven't looked into it) when something happens to my postfix config.
Though, no, i still don't see the issue with SMTP and anonymous connection, unless you mean anonymous sending. You don't have to block the port to solve that issue.
Darvond: It must be coded in something nobody wants to work with for those bounties.
OneFiercePuppy: I'm enjoying the idea that Valve hired half a dozen programming students and their stuff is all in C but every block ends with a goto pointed at another block. Or else Gaben was a personal friend of Larry Wall and hired him for it, so Wall programmed the client in C but somehow using Perl syntax.
Please, tell me more on this.
sanscript: Any sane admin would block access to p25.
In the early days these protocols were made with simple and open sharing in mind, though, the Internet changed that. But some years ago this blocking of p25 among others actually became a standard procedure in order to prevent abuse.
Btw; search for
nmap and you have a nice little power-tool at your hand ;-)
rtcvb32: nmap, ah yes, i'm aware of that tool. Been a while since i used it.
I'd honestly go for a shared key method, where public keys are set up and private keys for people on their computer. Then signing and encrypting all email and verifying (
at the server level). Yeah takes a little more processing power, but 99.99% of spam would die this way because it's not raw text. You can't really fool it, unless a key gets broken, in which case you give a new key or require updating the key to the next larger size every couple years.
Eh, if it became common practice, the pubkey would be available to the spammers the same avenue the email address is, which wouldn't solve anything. Sure, it'd solve the crap we're seeing now, but not for long. If the key is done privately, why not just give out the email privately as well? I've seen people have success with whitelisting email addresses, as well, and spam rarely comes from a known source (does happen, but much less common).
rtcvb32: nmap, ah yes, i'm aware of that tool. Been a while since i used it.
I'd honestly go for a shared key method, where public keys are set up and private keys for people on their computer. Then signing and encrypting all email and verifying (
at the server level). Yeah takes a little more processing power, but 99.99% of spam would die this way because it's not raw text. You can't really fool it, unless a key gets broken, in which case you give a new key or require updating the key to the next larger size every couple years.
sanscript: With pre-shared keys? I agree, but encrypting the mail itself (inside of the already encrypted communication) is rather tiresome, especially when very few uses it, like GnuPGP, so it's dependent on both A and B to use it.
Other than Protonmail I can't think of any "easy" solution if security and privacy is a must have...
If you're worried about the privacy of emails, you should be using external tools to encrypt the data within the email. Things setting on storage, if you're not the admin, tends to get pulled and looked at.