CVE-2026-45065: Symfony open redirect in UrlGenerator route validation

CVE-2026-45065 · Severity: medium · CVSS 6.1 · Published 2026-07-14

Symfony, a popular web application framework for PHP, contains a vulnerability in its URL generation component. An attacker could potentially trick the system into generating links that lead to malicious external websites instead of the intended internal pages. This could be used in phishing attacks to steal user credentials or redirect users to harmful content.

Technologies: symfony/routing (Packagist), symfony/symfony (Packagist). Vendors: Packagist, Symfony.

Quick answers

Is CVE-2026-45065 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-45065 being exploited in the wild.
How severe is CVE-2026-45065?
Medium severity, with a CVSS score of 6.1, published 14 July 2026.
Which products and versions are affected?
symfony/routing (Packagist) ECOSYSTEM:introduced=0,fixed=5.4.52; symfony/symfony (Packagist) ECOSYSTEM:introduced=0,fixed=5.4.52.
Is there a fix for CVE-2026-45065?
Yes. symfony/routing (Packagist): upgrade to 5.4.52 or later; symfony/symfony (Packagist): upgrade to 5.4.52 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-45065 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-45065?
Check whether you run symfony/routing (Packagist), symfony/symfony (Packagist) or Symfony Routing Component at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • symfony/routing (Packagist): upgrade to 5.4.52 or later
    composer require symfony/routing:^5.4.52
  • symfony/symfony (Packagist): upgrade to 5.4.52 or later
    composer require symfony/symfony:^5.4.52

Technical details

A vulnerability exists in the Symfony Routing component's UrlGenerator. The component validates route parameters against a pattern constructed as '^' plus the raw requirement plus '$'. When using ungrouped alternations in requirements (e.g., 'fr|en'), middle alternatives can match as unanchored substrings. This allows an attacker to provide a value such as '//evil.com' that satisfies a common requirement (like a locale) but results in the generation of a protocol-relative off-site URL. This is classified as an open redirect (CWE-601) caused by an incorrect regular expression (CWE-185). The issue is fixed in Symfony versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.

Affected products

  • Symfony Symfony < 5.4.52, >= 6.0.0-BETA1 < 6.4.40, >= 7.0.0-BETA1 < 7.4.12, >= 8.0.0-BETA1 < 8.0.12

Identifiers

  • CVE-2026-45065
  • GHSA-72xp-p242-47p9

Timeline

  • 2026-05-20: patched: Fixes released in versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12
  • 2026-07-14: advisory: CVE published by NVD

References

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