Vulnerability in Sensiolabs Symfony
CVE-2026-45066
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (25.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 25.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Sensiolabs Symfony
- Symfony Html-Sanitizer — versions >= 6.1.0-BETA1, < 6.4.40, >= 7.0.0-BETA1, < 7.4.12, >= 8.0.0-BETA1, < 8.0.12
- Symfony — versions >= 6.1.0-BETA1, < 6.4.40, >= 7.0.0-BETA1, < 7.4.12, >= 8.0.0-BETA1, < 8.0.12
Weakness classification (CWE)
References
- github.com/symfony/symfony/security/advisories/GHSA-qc95-4862-92fh (Patch, Vendor Advisory)
- github.com/symfony/symfony/commit/d506b556d3d3906f3e8660ad82257ce87edbaac4 (Patch)
- github.com/symfony/symfony/releases/tag/v6.4.40 (Product, Release Notes)
- github.com/symfony/symfony/releases/tag/v7.4.12 (Product, Release Notes)
- github.com/symfony/symfony/releases/tag/v8.0.12 (Product, Release Notes)
Frequently asked questions
- What is CVE-2026-45066?
- CVE-2026-45066 is a medium-severity vulnerability in Sensiolabs Symfony, classified under Incomplete List of Disallowed Inputs. CVSS score: 6.1/10. Published 2026-07-14.
- How severe is CVE-2026-45066?
- Medium severity. CVSS v3 base score is 6.1 out of 10.