System Information
Operating system: Windows-10-10.0.18362-SP0 64 Bits
Graphics card: GeForce RTX 2080 Ti/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 452.06

Blender Version
Broken: version: 2.90.0, branch: master, commit date: 2020-08-31 11:26, hash: rB0330d1af29c0
Worked: (newest version of Blender that worked as expected)

Short description of error
Hook Modifier Crash Blender when add an empty vertex group

Exact steps for others to reproduce the error

• Add a new vertex group in the default cube
• Add Hook modifier and link to any object and assign the empty group of vertices.
• Blender Crash

Note: If the group of vertices has any vertex assigned Blender no Crash.

PS: Blender 2.91 has the same error.