Firewall alert, Description: Suspiciously small datagram fragment. possibly a fragmentation attack

One user of PSB 12.01 is receiveing this warning: Firewall alert, Description: Suspiciously small datagram fragment. Possibly a fragmentation attack.

 

She´s connected to our LAN. The address a IPV6 (belongs to a printer which resides on the same LAN). No other user gets this message.

 

OS is Windows 7.

Comments

  • VadVad Posts: 1,051 F-Secure Employee

    Hello GoldenNugget,

     

    Please check in PSB GUI Settings window, Network Connections > Firewall > Settings tab > Firewall settings the parameter "Block IP fragments shorter than". What fragment size do you have? Default value is 128.

     

    Best regards,

    Vad 

  • Set as  128 byte.

  • VadVad Posts: 1,051 F-Secure Employee

    You can try to decrease it to 64 or 32 bytes for example, and check if it helps.

     

    Best regards,

    Vad

This discussion has been closed.