Public email servers working in 2020?

[bradetter]

Evidently, public email servers have tightened their security and caused problems for many IP cameras and NVRs.
I am still working with Amcrest support; however, I'm not very optimistic.

Has ANYONE been able to send emails to ANY email service lately?
I have tried both Yahoo and Gmail with all variations of ports, lowered security, etc.
It would help if the NVR generated some info in the system log for these types of issues.

Thanks in advance.
Brad

[amcrest168]

i'm able to send email notifications with a comcast.net email account.

[Revo2Maxx]

I am able to get Emails from my server.. gmail Sent me an email though an older System Recorder I have that don't seem to be an issue with gmail at this time yet I am waiting for that to change.. I didn't change over to my smtp server on my older machines just to see if they keep working with gmail or how long lol...

[plusfour]

Microsoft's servers still work since they ignore the invalid TLS handshake that the Amcrest devices are using. Long-term you'll have to either track down more and more obscure mailers that will still accept the invalid TLS handshake or set up your own mail relay that takes incoming messages from Amcrest devices and forwards them on using a correct TLS handshake.

[Z-Man]

Yahoo is still going.

[plusfour]

On the basis of "if they can't get their s**t together maybe we can get it together for them", I had a look at what it'd take to fix the TLS bug. The idea is to patch the binary so the SCSV signalling value gets turned into something else which is ignored by the server. The firmware is a squashfs busybox image which can be unpacked to yield the TLS code, which was in some subdirectory I can't remember, can't access the Linux box I did it on from here. To fix the bug, you patch out the cipher suite 0x56 0x00, e.g. by changing it to 0x57 0x00. However, the firmware is signed so you then have to patch out the signature check as well. I found the crypto code in IDA Pro but ran out of time, and was also somewhat less motivated about flashing patched custom-assembled firmware into the NVR that I need to use for security purposes.