Redragon Asura USB keyboard maps all Ctrl, Alt, Win keys to Shift_L

Status: This is fixed as of Kernel 4.18, see the accepted answer for details.

I just started using a Redragon Asura USB Keyboard. The keyboard works at a basic level, but unfortunately all the Ctrl, Alt keys and the Win key are mapped to the left shift key, which makes it quite hard to use.

The dmesg output is

[185765.848957] input: USB Keyboard as /devices/pci0000:00/0000:00:14.0/usb1/1-3/1-3:1.0/0003:0C45:760B.0022/input/input50
[185765.905395] hid-generic 0003:0C45:760B.0022: input,hidraw3: USB HID v1.11 Keyboard [USB Keyboard] on usb-0000:00:14.0-3/input0
[185765.949342] input: USB Keyboard as /devices/pci0000:00/0000:00:14.0/usb1/1-3/1-3:1.1/0003:0C45:760B.0023/input/input51
[185766.009474] hid-generic 0003:0C45:760B.0023: input,hiddev0,hidraw4: USB HID v1.11 Keyboard [USB Keyboard] on usb-0000:00:14.0-3/input1

I've started debugging the key presses using xev, and I get the exact same key mapping for those keys. I might've mixed the KeyPress and KeyRelease events, but all in all they are the same ( see at the end of the post ).

What can I do to properly map the Ctrl, Alt and Win keys?

Left alt:

KeyRelease event, serial 36, synthetic NO, window 0x3200001,
    root 0xd7, subw 0x0, time 185237066, (307,429), root:(2272,538),
    state 0x1, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XFilterEvent returns: False

Left ctrl:

KeyPress event, serial 36, synthetic NO, window 0x3200001,
    root 0xd7, subw 0x0, time 185265721, (443,237), root:(2408,346),
    state 0x0, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

Left shift:

KeyRelease event, serial 36, synthetic NO, window 0x3200001,
    root 0xd7, subw 0x0, time 185303441, (436,539), root:(2401,648),
    state 0x1, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XFilterEvent returns: False

Win key:

KeyPress event, serial 36, synthetic NO, window 0x3200001,
    root 0xd7, subw 0x0, time 185327465, (399,367), root:(2364,476),
    state 0x0, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

Right Alt:

KeyPress event, serial 36, synthetic NO, window 0x3200001,
root 0xd7, subw 0x0, time 185361768, (348,141), root:(2313,250),
    state 0x0, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

Right ctrl:

KeyPress event, serial 36, synthetic NO, window 0x3200001,
    root 0xd7, subw 0x0, time 185401328, (598,415), root:(2563,524),
    state 0x0, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

Edit: indeed, the keyboard shows up as two USB devices. I've uploaded the HID descriptors from /sys/debug/kernel/hid at

• https://pastebin.com/4VwDKRvU
• https://pastebin.com/CrBVRFBj