Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 5.4.53, 6.4.41, 7.4.13, and 8.0.13, UrlGenerator::doGenerate() used strtr() dot-segment encoding that skipped every other chained ../ or ./ segment, allowing attacker-controlled route parameters to generate URLs that collapse to a different path under RFC 3986 normalization. This issue is fixed in versions 5.4.53, 6.4.41, 7.4.13, and 8.0.13.
https://github.com/symfony/symfony/security/advisories/GHSA-h5x3-xfc9-m39h
https://github.com/symfony/symfony/releases/tag/v7.4.13
https://github.com/symfony/symfony/releases/tag/v6.4.41
https://github.com/symfony/symfony/releases/tag/v5.4.53
https://github.com/symfony/symfony/commit/4b63c3a3f7af04ecd79c89a594b0b02a01990b1d
Published: 2026-07-14
Updated: 2026-07-15
Base Score: 6.4
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:N
Severity: Medium
Base Score: 6.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Severity: Medium
Base Score: 5.1
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
Severity: Medium
EPSS: 0.00026