An issue was discovered with ImageMagick 7.1.0-4 via Division by zero in function ReadEnhMetaFile of coders/emf.c.
### ImageMagick version

7.1.0

### Operating system

All system

### Operating system, version and so on

All system，the latest version

### Description

pBits can be controlled by an attacker，a division-by-zero exception can happen in function ReadEnhMetaFile() of coders/emf.c at line 428,431.  
![222](https://user-images.githubusercontent.com/20721416/130314910-b71d616a-6ec9-4d0e-885b-cad8c46fd4d3.png)



### Steps to Reproduce

As is mentioned in the description.

### Images

_No response_
Division by zero in ReadEnhMetaFile() of coders/emf.c
This is a GitHub Issue
repo:ImageMagick
owner:ImageMagick
Title : Division by zero in ReadEnhMetaFile() of coders/emf.c
Issue date:

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### ImageMagick version

7.1.0

### Operating system

All system

### Operating system, version and so on

All system，the latest version

### Description

pBits can be controlled by an attacker，a division-by-zero exception can happen in function ReadEnhMetaFile() of coders/emf.c at line 428,431.  
![222](https://user-images.githubusercontent.com/20721416/130314910-b71d616a-6ec9-4d0e-885b-cad8c46fd4d3.png)



### Steps to Reproduce

As is mentioned in the description.

### Images

_No response_
--- end body ---
