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

Forum Discussion

2 Replies

  • David_226's avatar
    David_226
    Icon for Nimbostratus rankNimbostratus
    Feb 13, 2023

    I check the recommandations in this link but everythink recommanded is ok.

    i dont know if the last sentence in error "your acces to submit messages to this email system has been rejected" and "Unable to relay for user@sierracollege.edu" are caused by the same issu.

    Thanks

     

    • Paulius's avatar
      Paulius
      Icon for MVP rankMVP
      Feb 13, 2023

      David_226 I would recommend performing a tcpdump on the F5 to ensure that you are sending the message to the destination SMTP relay server as well as a capture on that server to ensure you are receiving the relay.