Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, HtmlSanitizer URL sanitization can allow off-allowlist URLs through allowLinkHosts() or allowMediaHosts() because UrlSanitizer::parse() follows RFC 3986 while browsers follow WHATWG URL parsing, and because <area href> is checked against the media policy rather than the link policy. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.
Advisories
Source ID Title
Debian DSA Debian DSA DSA-6312-1 symfony security update
Github GHSA Github GHSA GHSA-qc95-4862-92fh Symfony has an HtmlSanitizer allowLinkHosts() / allowMediaHosts() Bypass via URL-Parser Differentials and <area> Misclassification
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 05 Aug 2026 10:45:00 +0000

Type Values Removed Values Added
First Time appeared Symfony
Symfony html-sanitizer
Symfony symfony
Vendors & Products Symfony
Symfony html-sanitizer
Symfony symfony

Thu, 16 Jul 2026 15:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 14 Jul 2026 18:15:00 +0000

Type Values Removed Values Added
Description Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, HtmlSanitizer URL sanitization can allow off-allowlist URLs through allowLinkHosts() or allowMediaHosts() because UrlSanitizer::parse() follows RFC 3986 while browsers follow WHATWG URL parsing, and because <area href> is checked against the media policy rather than the link policy. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.
Title Symfony: HtmlSanitizer allowLinkHosts() / allowMediaHosts() Bypass via URL-Parser Differentials and <area> Misclassification
Weaknesses CWE-184
CWE-436
References
Metrics cvssV4_0

{'score': 2.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-07-16T14:29:30.033Z

Reserved: 2026-05-08T18:45:10.096Z

Link: CVE-2026-45066

cve-icon Vulnrichment

Updated: 2026-07-16T14:29:23.755Z

cve-icon NVD

Status : Analyzed

Published: 2026-07-14T18:17:16.703

Modified: 2026-07-16T15:16:31.367

Link: CVE-2026-45066

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-05T10:23:26Z

Weaknesses