CVE-2026-45066
Symfony: HtmlSanitizer allowLinkHosts() / allowMediaHosts() Bypass via URL-Parser Differentials and <area> Misclassification
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.
INFO
Published Date :
July 14, 2026, 6:17 p.m.
Last Modified :
July 16, 2026, 3:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | LOW | [email protected] |
Solution
- Update Symfony to version 6.4.40 or later.
- Update Symfony to version 7.4.12 or later.
- Update Symfony to version 8.0.12 or later.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-45066.
| URL | Resource |
|---|---|
| https://github.com/symfony/symfony/commit/d506b556d3d3906f3e8660ad82257ce87edbaac4 | Patch |
| https://github.com/symfony/symfony/releases/tag/v6.4.40 | Product Release Notes |
| https://github.com/symfony/symfony/releases/tag/v7.4.12 | Product Release Notes |
| https://github.com/symfony/symfony/releases/tag/v8.0.12 | Product Release Notes |
| https://github.com/symfony/symfony/security/advisories/GHSA-qc95-4862-92fh | Patch Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-45066 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-45066
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-45066 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-45066 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 16, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-45066', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-16T14:29:18.947584Z'} -
Initial Analysis by [email protected]
Jul. 15, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Added CPE Configuration OR *cpe:2.3:a:sensiolabs:symfony:*:*:*:*:*:*:*:* versions from (including) 7.0.0 up to (excluding) 7.4.12 *cpe:2.3:a:sensiolabs:symfony:*:*:*:*:*:*:*:* versions from (including) 8.0.0 up to (excluding) 8.0.12 *cpe:2.3:a:sensiolabs:symfony:*:*:*:*:*:*:*:* versions from (including) 6.1.0 up to (excluding) 6.4.40 Added Reference Type GitHub, Inc.: https://github.com/symfony/symfony/commit/d506b556d3d3906f3e8660ad82257ce87edbaac4 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/symfony/symfony/releases/tag/v6.4.40 Types: Product, Release Notes Added Reference Type GitHub, Inc.: https://github.com/symfony/symfony/releases/tag/v7.4.12 Types: Product, Release Notes Added Reference Type GitHub, Inc.: https://github.com/symfony/symfony/releases/tag/v8.0.12 Types: Product, Release Notes Added Reference Type GitHub, Inc.: https://github.com/symfony/symfony/security/advisories/GHSA-qc95-4862-92fh Types: Patch, Vendor Advisory -
New CVE Received by [email protected]
Jul. 14, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'symfony', 'product': 'symfony', 'versions': [{'status': 'affected', 'version': '>= 6.1.0-BETA1, < 6.4.40'}, {'status': 'affected', 'version': '>= 7.0.0-BETA1, < 7.4.12'}, {'status': 'affected', 'version': '>= 8.0.0-BETA1, < 8.0.12'}]}, {'vendor': 'symfony', 'product': 'html-sanitizer', 'versions': [{'status': 'affected', 'version': '>= 6.1.0-BETA1, < 6.4.40'}, {'status': 'affected', 'version': '>= 7.0.0-BETA1, < 7.4.12'}, {'status': 'affected', 'version': '>= 8.0.0-BETA1, < 8.0.12'}]}] 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. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-184 Added CWE CWE-436 Added Reference https://github.com/symfony/symfony/commit/d506b556d3d3906f3e8660ad82257ce87edbaac4 Added Reference https://github.com/symfony/symfony/releases/tag/v6.4.40 Added Reference https://github.com/symfony/symfony/releases/tag/v7.4.12 Added Reference https://github.com/symfony/symfony/releases/tag/v8.0.12 Added Reference https://github.com/symfony/symfony/security/advisories/GHSA-qc95-4862-92fh