Data Destruction. Part 2
Disabling Decryption Keys and Physically Destroying Digital Storage Devices
Sometimes you don’t need to dеlete the data itself — it’s enough to make access to it technically impossible. One of the most reliable ways is to disable the encryption keys. In practice, this can be even more effective than physically destroying the device, especially if you use LUKS encryption in Linux.
With LUKS, data is encrypted using a randomly generated master key. This master key is itself encrypted using a user password. The systеm allows up to 8 separate passwords (key slots from 0 to 7), each unlocking the same master key.
If you disable all key slots, the master key becomes inaccessible. The data is still physically present, but it cannot be decrypted — not even by professionals. You can verify the state of the slots using the Linux terminal:
sudo cryptsetup luksDump /dev/sdX
If all key slots show as DISABLED, it means no password can be used to decrypt the data. Unlike simply “forgetting” a password, this method is technically provable — making it far more secure under pressure.
To disable a specific key slot, use the following command:
sudo cryptsetup luksKillSlot /dev/sdX N
Where N is the slot number from 0 to 7.
Physical Destruction of the Drive
This is the most reliable and final method — physically destroy the storage device. If the memory chip is damaged, data recovery is impossible, even in forensic labs.
That’s why experienced users often boot their systems from USB sticks instead of internal hard drives. A USB flash drive can be quickly removed and destroyed if necessary — which is essential for handling sensitive or critical data.
How a Flash Drive Works
A flash drive typically consists of three main parts:
- The outer casing (plastic or metal)
- The USB connector
- A small PCB with two chips: a controller and a memory chip
Your goal is to damage the memory chip. Once it’s cracked, burnt, or physically destroyed, the data is gone — permanently. Even professional recovery labs cannot restore it.
Flash Drive Selection Tips
- Use cheap plastic models with large memory chips (easier to damage)
- Avoid “military-grade” or ultra-durable drives, especially from brands like Kingston
- Look for drives with a detachable or easily reassembled case
- You can also transplant the internal board into a basic plastic case for quick access
Destruction Methods
- Break the board with your hands
- Use pliers, cutters, or scissors
- Burn the chip with a lighter or apply high heat
- Scratch or puncture the contacts with a knife or needle
Summary: Data Destruction Methods Ranking
- Physical destruction of the device — 100% guaranteed, immediate elimination
- Disabling all encryption key slots — fast, provable, and highly effective
- Intentional loss of a strong password — can work, but risky under pressure
- Simple disk overwriting — basic protection, effective only against non-experts
The best approach is to combine multiple methods. For example:
- Set up a LUKS-encrypted partition
- Store the key separately from the device
- Disable all key slots when necessary
- Physically destroy the USB drive if needed
Only a multi-layered approach ensures your data will never be recovered — no matter who gains access to the hardware.