Environment:

Kali version: 2026.1rc3 (latest snapshot as of April 2026)
Architecture: amd64
Installation method: Offline installer ISO
Hardware: Custom desktop, 3TB HDD (sdc), WiFi via USB adapter (rt2870 firmware)
Tested with: Two different USB drives (Kingston DataTraveler 62GB, WD 2TB external)

Errors encountered in order:

cdrom:// fetch failures during "Select and install software" — apt could see the package index but failed to read every .deb from the USB with "Failed to fetch cdrom://[Kali GNU/Linux 2026.1rc3 Kali-last-snapshot]" for all packages. Packages were confirmed present on USB via ls /cdrom/pool/main. Bind mounting /cdrom to /target/media/cdrom0 did not resolve it.
"Unable to install busybox" — When retrying Install the base system after repartitioning, debootstrap failed immediately with "An error was returned while trying to install the busybox package onto the target system."
"Asked to install suite kali-rolling, but got (codename: ) from mirror" — On subsequent attempts, debootstrap connected to the network mirror but received an empty codename response, causing immediate failure.
Filesystem corruption cascade — The repeated failed installs caused ext4 filesystem errors on the target partition (sdc2), which triggered automatic remount as read-only (errors=remount-ro,emergency_ro), requiring e2fsck between attempts.
debconf-apt-progress failures — All Python-based apt tools failed inside the installer environment with ImportError: /usr/lib/python3/dist-packages/apt_pkg.cpython-313-x86_64-linux-gnu.so: file too short — both .so files were 0 bytes.

Workaround: Downloading and installing from the 2024.2 offline installer ISO on identical hardware completed successfully with no errors.
Steps to reproduce:

Download latest Kali offline installer ISO
Write to USB with dd if=kali.iso of=/dev/sdX bs=4M status=progress oflag=sync
Boot and proceed through installer to "Install the base system" or "Select and install software"
Observe failures as described above