Improper input validation in Dompdf
CVE-2026-56722
Dompdf is an HTML to PDF converter for PHP. In versions 3.15 and prior, aAn attacker who controls the HTML input can bypass this restriction by embedding a target file path inside an SVG image delivered through a data: URI, because dompdf processes the SVG twice and the second pass does not enforce the same protections as the first. When rendering, dompdf hands the SVG to the separate php-svg-lib library with external references forced on, and that library has no knowledge of the chroot directory, blocks only the phar:// scheme, and ultimately reads the referenced file with no path or protocol validation. This lets an external, unauthenticated attacker read arbitrary image files from the server's file system in the default configuration. This issue has been fixed in version 3.16.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
EPSS: 0.003 (25.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
Affected products
- Dompdf — versions < 3.1.6
- Dompdf_project Dompdf
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-56722?
- CVE-2026-56722 is a medium-severity vulnerability in Dompdf, classified under Improper Input Validation. CVSS score: 5.3/10. Published 2026-07-28.
- How severe is CVE-2026-56722?
- Medium severity. CVSS v3 base score is 5.3 out of 10.