What does "bunged to the eyes with rust and penicillin" mean from the poem unlucky boat by george mackay brown

From the poem Unlucky Boat by George Mackay Brown, the line "bunged to the eyes with rust and penicillin" means the boat is old and sunken with lots of holes covered by rust and molds are starting to live on it for the longest period it remains stagnant and starts decaying.

C. The long and difficult journey reflects how strong and enduring Gilgamesh is.