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✏️ Editing: policy.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE policymap [
<!ELEMENT policymap (policy)*>
<!ATTLIST policymap xmlns CDATA #FIXED "">
<!ELEMENT policy EMPTY>
<!ATTLIST policy xmlns CDATA #FIXED "">
<!ATTLIST policy domain NMTOKEN #REQUIRED>
<!ATTLIST policy name NMTOKEN #IMPLIED>
<!ATTLIST policy pattern CDATA #IMPLIED>
<!ATTLIST policy rights NMTOKEN #IMPLIED>
<!ATTLIST policy stealth NMTOKEN #IMPLIED>
<!ATTLIST policy value CDATA #IMPLIED>
]>
<!--
  Creating a security policy that fits your specific local environment
  before making use of ImageMagick is highly advised. You can find guidance on
  setting up this policy at https://imagemagick.org/script/security-policy.php,
  and it's important to verify your policy using the validation tool located
  at https://imagemagick-secevaluator.doyensec.com/.

Open ImageMagick security policy:

The default policy for ImageMagick installations is the open security
  policy. This policy is designed for usage in secure settings like those
  protected by firewalls or within Docker containers. Within this framework,
  ImageMagick enjoys broad access to resources and functionalities. This policy
  provides convenient and adaptable options for image manipulation. However,
  it's important to note that it might present security vulnerabilities in
  less regulated conditions. Thus, organizations should thoroughly assess
  the appropriateness of the open policy according to their particular use
  case and security prerequisites.

ImageMagick security policies in a nutshell:

Domains include system, delegate, coder, filter, module, path, or resource.

Rights include none, read, write, execute and all.  Use | to combine them,
  for example: "read | write" to permit read from, or write to, a path.

Use a glob expression as a pattern.

Suppose we do not want users to process MPEG video images, use this policy:

Here we do not want users reading images from HTTP:

The /repository file system is restricted to read only.  We use a glob
  expression to match all paths that start with /repository:

Prevent users from executing any image filters:

Cache large images to disk rather than memory:

Use the default system font unless overridden by the application:

Define arguments for the memory, map, area, width, height and disk resources
  with SI prefixes (.e.g 100MB).  In addition, resource policies are maximums
  for each instance of ImageMagick (e.g. policy memory limit 1GB, -limit 2GB
  exceeds policy maximum so memory limit is 1GB).

Rules are processed in order.  Here we want to restrict ImageMagick to only
  read or write a small subset of proven web-safe image types:

See https://imagemagick.org/script/security-policy.php for a deeper
  understanding of ImageMagick security policies.
-->
<policymap>
  <policy domain="Undefined" rights="none"/>
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
</policymap>

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