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Looks like a device on the path through the VPN connection on which the oracle connection fails is dropping all packets that have the URG flag set.
From my understanding, segments 13 and 14 say "I have received the segment 455 and also the segments from 456 to 626". So why after this the client starts the Retransmission of the TCP segment 626 ?
TCP does not handle segments, it handles streams of bytes. The ACK meaning, I have received up till (not including) this byte offset, so please send me the bytes from this offset forward. In this case, it wants to receive the bytes at offset 455 onwards. The SACK block SLE=456, SRE=626 tell the sending side that bytes 456 till 626 are already received. So theoreticaaly only 1 byte needs to be retransmitted, but in practice a block of data is retransmitted, as can be seen in this trace.