Since Rust doesn't run within a VM (ala Java), I don't think there's a way to set explicit memory limits, but there could be options added to limit the width and height. There is an existing CLI option, --timeout, which will limit the wall time oxipng will spend on a file.

I'm reading that these attacks can also happen through excessively large iCCP chunks, zTXt chunks, and iTXt chunks, so ensuring oxipng protects against these (by default) would be a good addition as well.

For anyone looking for a temporary workaround, you can use systemd-run to do resource limiting, e.g.

systemd-run --user --wait -Pp MemoryHigh=5% oxipng input.png output.png

You can set -p MemoryMax=10% as well if you want the transient service to exit if its memory usage creeps too high (MemoryHigh is only a soft cap, and oxipng's memory use does tend to increase the longer it runs).