CVE-2026-45066

Symfony: HtmlSanitizer allowLinkHosts() / allowMediaHosts() Bypass via URL-Parser Differentials and <area> Misclassification

Published: Jul 14, 2026Updated: Jul 16, 2026 Sources: CVE List NVDCWE-184

6.1MEDIUM

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:RUser Interaction

Required

Scope

S:CScope

Changed

Impact

C:LConfidentiality

Low

I:LIntegrity

Low

A:NAvailability

None

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Weaknesses

CWE-184 CWE-436

Affected Products

symfony

oss-projectaka symfony framework, twig (related)

symfonyLibrary

OSS Libraries / web-framework

html-sanitizerLibrary

OSS Libraries / web-framework

sensiolabs

oss-project

symfonyLibraryLibrary

OSS Libraries / generic-library

Exploitability

Official Patch Available

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References

https://github.com/symfony/symfony/security/advisories/GHSA-qc95-4862-92fh

github.com

https://github.com/symfony/symfony/commit/d506b556d3d3906f3e8660ad82257ce87edbaac4

github.com

https://github.com/symfony/symfony/releases/tag/v6.4.40

github.com

and 2 more references View all →

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