Php dompdf: Dompdf is an HTML to PDF converter for PHP. (CVE-2026-55554)
Dompdf is an HTML to PDF converter for PHP. In versions 3.15 and prior, the validateLocalUri() method enforces chroot boundaries with a strpos() prefix check after normalizing paths with realpath() . Because normalization strips the trailing directory separator from $chrootPath , the check only verifies that $chrootPath is a string prefix of $realfile, so a chroot of /var/www also matches sibling directories like /var/www2 , /var/www-admin, or /var/www_backup. An attacker who controls part of the rendered HTML could exploit this to escape the chroot and read sensitive files outside the allowed directory. This issue has been fixed in version 3.16.
AI Analysis
Technical Summary
The vulnerability in Dompdf's validateLocalUri() method stems from improper enforcement of chroot boundaries. After normalizing file paths with realpath(), the code checks if the file path starts with the chroot path using strpos(), but does not append a trailing slash to the chroot path. This allows paths in directories with names that start with the chroot path string but are outside the intended directory (e.g., /var/www2 when chroot is /var/www) to pass the check. Consequently, attacker-controlled document paths can bypass local file restrictions and access files outside the chroot. The issue affects Dompdf versions prior to 3.1.6.
Potential Impact
An attacker who can control part of the HTML rendered by Dompdf can bypass the intended chroot restrictions and access files outside the allowed directories. This may lead to unauthorized disclosure of sensitive local files. The severity is rated low, and there are no known exploits in the wild at this time.
Mitigation Recommendations
A fix is available in Dompdf version 3.1.6 or later. Users should upgrade to version 3.1.6 or newer to address this vulnerability. Until patched, carefully validate and sanitize any user-controlled input that affects file paths or document content to minimize risk.
Php dompdf: Dompdf is an HTML to PDF converter for PHP. (CVE-2026-55554)
Description
Dompdf is an HTML to PDF converter for PHP. In versions 3.15 and prior, the validateLocalUri() method enforces chroot boundaries with a strpos() prefix check after normalizing paths with realpath() . Because normalization strips the trailing directory separator from $chrootPath , the check only verifies that $chrootPath is a string prefix of $realfile, so a chroot of /var/www also matches sibling directories like /var/www2 , /var/www-admin, or /var/www_backup. An attacker who controls part of the rendered HTML could exploit this to escape the chroot and read sensitive files outside the allowed directory. This issue has been fixed in version 3.16.
CVSS v3.1
Score 7.5high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in Dompdf's validateLocalUri() method stems from improper enforcement of chroot boundaries. After normalizing file paths with realpath(), the code checks if the file path starts with the chroot path using strpos(), but does not append a trailing slash to the chroot path. This allows paths in directories with names that start with the chroot path string but are outside the intended directory (e.g., /var/www2 when chroot is /var/www) to pass the check. Consequently, attacker-controlled document paths can bypass local file restrictions and access files outside the chroot. The issue affects Dompdf versions prior to 3.1.6.
Potential Impact
An attacker who can control part of the HTML rendered by Dompdf can bypass the intended chroot restrictions and access files outside the allowed directories. This may lead to unauthorized disclosure of sensitive local files. The severity is rated low, and there are no known exploits in the wild at this time.
Mitigation Recommendations
A fix is available in Dompdf version 3.1.6 or later. Users should upgrade to version 3.1.6 or newer to address this vulnerability. Until patched, carefully validate and sanitize any user-controlled input that affects file paths or document content to minimize risk.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-wvh6-f5jh-8gw4
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-55554"]
- Ecosystems
- ["Packagist"]
- Database Specific Severity
- LOW
- Cvss Version
- 4.0
Threat ID: 6a6150ed9c2644c7f8da2c9e
Added to database: 07/22/2026, 23:23:25 UTC
Last enriched: 07/22/2026, 23:40:32 UTC
Last updated: 09/05/2026, 10:52:10 UTC
Views: 89
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