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

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andresneri1's avatar
andresneri1
Icon for Altostratus rankAltostratus
Jul 22, 2022
Solved

iRule for TCP/SMTP and extract fields "MAIL FROM: "

I need a iRule to extract fields from "MAIL FROM:" in an SMTP traffic. for example: S->220 mail.mycompany.com Microsoft ESMTP MAIL Service ready ... C->EHLO 172.16.1.100 S->250-mail.mycompany.com...
application delivery
iRules TCP::payload TCP::collect
Kevin_Davies's avatar
Kevin_Davies
Icon for Nacreous rankNacreous
Jul 24, 2022

There are a number iRule implementations of SMTP proxies. I have linked a couple below. I have also implemented a proxy for SMTP myself based on haproxy's proxy protocol. I linked another example as well.  That should give you plenty of guidance on how to read these headers. If you are still stuck after reading them, reach out.

SMTP Proxy - DevCentral (f5.com)
SMTP filter and forward proxy - DevCentral (f5.com)
Proxy Protocol Receiver - DevCentral (f5.com)