Mar 27, 2026 - For details about updated CVE-2025-53521 (BIG-IP APM vulnerability), refer to K000156741.

Forum Discussion

Sam_Hall's avatar
Sam_Hall
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Jul 11, 2017

Using STARTTLS in System | Configuration : Device : SMTP

Looking at the configuration options, it seems that STARTTLS is not supported, only implicit encryption is supported (generally on port 465). This is going to sound a bit goofy, but despite the notes...
application delivery
LTM
Sam_Hall's avatar
Sam_Hall
Icon for Nimbostratus rankNimbostratus
Jul 13, 2017

It seems STARTTLS is not the issue, STARTTLS works just fine despite the lack of documentation. Our production LTM is refusing to send credentials before trying to send the email. For that issue I'm opening a support case.