vboximg-mount --image fc714048-2d6b-42e8-b455-e95725b6138d --list
(a VMDK from a VBoxManage export/import)
---
vboximg-mount --image fc714048-2d6b-42e8-b455-e95725b6138d --list

Virtual disk image:

   Base: /home/vms/pydev_vivo_1017/pydev_vivo_0620-disk002.vmdk
   UUID: fc714048-2d6b-42e8-b455-e95725b6138d

Partition                        Boot  Start  Sectors     Size   Offset  Type          
pydev_vivo_0620-disk002.vmdk(0)         2048  125827072  59.9G  1048576  Linux native  
---
vboximg-mount -i 9517fcf0-c5c9-4edf-8631-ca78e15b88ad m
---
ls -al m
total 14992600
drwxr-xr-x 2 root   root              0 Jan  1  1970 .
drwx------ 4 amo    amo            4096 Nov 29 19:21 ..
lr--r--r-- 1 root   root              0 Nov 29 19:34 pydev_vivo_0620-disk001.vmdk -> /home/vms/pydev_vivo_1017/pydev_vivo_0620-disk001.vmdk
-rw-r--r-- 1 nobody nogroup 42949672960 Nov 29 19:35 vhdd
-rw-rw-rw- 1 root   root    36029168640 Jan  1  1970 vol0
-rw-rw-rw- 1 root   root     6913969664 Jan  1  1970 vol1
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sudo mount m/vol0 /mnt
mount: /mnt: cannot mount m/vol0 read-only.

============================
host is Linux Debian 10.6

module:
ls -al  /usr/lib/virtualbox/vboximg-mount
-rwxr-xr-x 1 root root 122952 Oct 15 17:24 /usr/lib/virtualbox/vboximg-mount
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VBoxManage --version
6.1.16r140961
---
from inside the VM (Debian bullseye/sid):

fdisk -l /dev/sda
Disk /dev/sda: 40 GiB, 42949672960 bytes, 83886080 sectors
Disk model: VBOX HARDDISK   
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x7ccde131

Device     Boot    Start      End  Sectors  Size Id Type
/dev/sda1           2048 70371517 70369470 33.6G 83 Linux
/dev/sda2       70371518 83875364 13503847  6.4G 82 Linux swap / Solaris
---