Some more info:On Ubuntu 21.04 the bug is not present: bash has version "5.1-2ubuntu1" and libc6 has version "2.33-0ubuntu5".
- Bug#1008235: Acknowledgement (bash: corrupting variable... Leszek Dubiel
- Bug#1008235: Acknowledgement (bash: corrupting var... Eduardo Bustamante
- Bug#1008235: Acknowledgement (bash: corrupting... Leszek Dubiel
- Bug#1008235: Acknowledgement (bash: corrup... Leszek Dubiel
- Bug#1008235: Acknowledgement (bash: corrup... Leszek Dubiel