name : policy-websafe.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/. Web-safe ImageMagick security policy: This security protocol designed for web-safe usage focuses on situations where ImageMagick is applied in publicly accessible contexts, like websites. It deactivates the capability to read from or write to any image formats other than web-safe formats like GIF, JPEG, and PNG. Additionally, this policy prohibits the execution of image filters and indirect reads, thereby thwarting potential security breaches. By implementing these limitations, the web-safe policy fortifies the safeguarding of systems accessible to the public, reducing the risk of exploiting ImageMagick's capabilities for potential attacks. --> <policymap> <!-- Set maximum parallel threads. --> <policy domain="resource" name="thread" value="2"/> <!-- Set maximum time in seconds. When this limit is exceeded, an exception is thrown and processing stops. --> <policy domain="resource" name="time" value="60"/> <!-- Set maximum number of open pixel cache files. When this limit is exceeded, any subsequent pixels cached to disk are closed and reopened on demand. --> <policy domain="resource" name="file" value="768"/> <!-- Set maximum amount of memory in bytes to allocate for the pixel cache from the heap. When this limit is exceeded, the image pixels are cached to memory-mapped disk. --> <policy domain="resource" name="memory" value="256MiB"/> <!-- Set maximum amount of memory map in bytes to allocate for the pixel cache. When this limit is exceeded, the image pixels are cached to disk. --> <policy domain="resource" name="map" value="512MiB"/> <!-- Set the maximum width * height of an image that can reside in the pixel cache memory. Images that exceed the area limit are cached to disk. --> <policy domain="resource" name="area" value="16KP"/> <!-- Set maximum amount of disk space in bytes permitted for use by the pixel cache. When this limit is exceeded, the pixel cache is not be created and an exception is thrown. --> <policy domain="resource" name="disk" value="1GiB"/> <!-- Set the maximum length of an image sequence. When this limit is exceeded, an exception is thrown. --> <policy domain="resource" name="list-length" value="16"/> <!-- Set the maximum width of an image. When this limit is exceeded, an exception is thrown. --> <policy domain="resource" name="width" value="4KP"/> <!-- Set the maximum height of an image. When this limit is exceeded, an exception is thrown. --> <policy domain="resource" name="height" value="4KP"/> <!-- Periodically yield the CPU for at least the time specified in milliseconds. --> <policy domain="resource" name="throttle" value="2"/> <!-- Do not create temporary files in the default shared directories, instead specify a private area to store only ImageMagick temporary files. --> <!-- <policy domain="resource" name="temporary-path" value="/magick/tmp/"/> --> <!-- Force memory initialization by memory mapping select memory allocations. --> <policy domain="cache" name="memory-map" value="anonymous"/> <!-- Ensure all image data is fully flushed and synchronized to disk. --> <policy domain="cache" name="synchronize" value="true"/> <!-- Replace passphrase for secure distributed processing --> <!-- <policy domain="cache" name="shared-secret" value="secret-passphrase" stealth="true"/> --> <!-- Do not permit any delegates to execute. --> <policy domain="delegate" rights="none" pattern="*"/> <!-- Do not permit any image filters to load. --> <policy domain="filter" rights="none" pattern="*"/> <!-- Don't read/write from/to stdin/stdout. --> <policy domain="path" rights="none" pattern="-"/> <!-- don't read sensitive paths. --> <policy domain="path" rights="none" pattern="/etc/*"/> <!-- Indirect reads are not permitted. --> <policy domain="path" rights="none" pattern="@*"/> <!-- Deny all image modules and specifically exempt reading or writing web-safe image formats. --> <policy domain="module" rights="none" pattern="*" /> <policy domain="module" rights="read | write" pattern="{BMP,GIF,JPEG,PNG,TIFF,WEBP}"/> <policy domain="module" rights="read | write" pattern="{MPC}" stealth="true"/> <policy domain="module" rights="write" pattern="{JSON,INFO,PNM,PS}"/> <!-- This policy sets the number of times to replace content of certain memory buffers and temporary files before they are freed or deleted. --> <policy domain="system" name="shred" value="1"/> <!-- Enable the initialization of buffers with zeros, resulting in a minor performance penalty but with improved security. --> <policy domain="system" name="memory-map" value="anonymous"/> <!-- Set the maximum amount of memory in bytes that are permitted for allocation requests. --> <policy domain="system" name="max-memory-request" value="256MiB"/> </policymap>