This issue has been fixed in the Ubuntu package : https://bugs.launchpad.net/ubuntu/+source/busybox/+bug/1753572
Regarding debirf, my workaround for now is to replace busybox by the Ubuntu package inside the debirf initrd. rescue/modules/fix-busybox : #!/bin/bash -e latest_version=$(curl -fSsL https://fr.archive.ubuntu.com/ubuntu/pool/universe/b/busybox/ | \ awk '/busybox/ {match($0, /_([[:digit:]\.]+-[[:digit:]]+ubuntu[[:digit:]\.]+)_amd64/, vers); if (vers[1]) print vers[1] }' | \ sort -h | tail -n 1) curl -fSsL -o "${DEBIRF_ROOT}/tmp/busybox-static.deb" https://fr.archive.ubuntu.com/ubuntu/pool/main/b/busybox/busybox-static_${latest_version}_amd64.deb debirf_exec dpkg -i /tmp/busybox-static.deb && rm -f /tmp/busybox-static.deb
