Packagist/symfony/symfony CVE-2026-45753: medium 6.1, EPSS 0.34%

Symfony's HtmlSanitizer UrlAttributeSanitizer Omits action/formaction/poster/cite — `javascript`: URI Survives Sanitization (XSS)

Action: Upgrade symfony/symfony to 6.4.40 or later.

composer require symfony/symfony:6.4.40

composer require symfony/symfony:7.4.12

composer require symfony/symfony:8.0.12

Affected

Fixed versions

Sources

• osv: GHSA-hhg7-c65m-h7ff#Packagist/symfony/symfony
• nvd: CVE-2026-45753
• https://github.com/symfony/symfony/security/advisories/GHSA-hhg7-c65m-h7ff
• https://github.com/symfony/symfony/commit/26a598fcfc4f903cc55ff202f642ee621839825e
• https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/html-sanitizer/CVE-2026-45753.yaml
• https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2026-45753.yaml
• https://github.com/symfony/symfony
• https://symfony.com/cve-2026-45753

CVE-2026-45753 · published 2026-05-28T16:43:27Z · modified 2026-09-10T03:51:06.023129963Z · JSON