# CVE-2026-47767: Symfony Runtime environment variable manipulation via query string bypass

Source: https://junglewise.ai/threats/cve-2026-47767-symfony-runtime-environment-variable-manipulation-via-query  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-14. Updated: 2026-07-14  
License: CC BY 4.0 with a link back

CVE-2026-47767 · Severity: medium · CVSS 4 · Published 2026-07-14

Symfony is a popular PHP framework used to build web applications. A vulnerability in its runtime component allows an attacker to manipulate application settings, such as enabling debug mode or changing the environment configuration, via a specially crafted web request. This could lead to the exposure of sensitive system information or unauthorized changes to how the application behaves.

Technologies: [symfony/symfony (Packagist)](https://junglewise.ai/threats/technologies/symfony-symfony). Vendors: [Packagist](https://junglewise.ai/threats/vendors/packagist), [Symfony](https://junglewise.ai/threats/vendors/symfony).

## Quick answers

**Is CVE-2026-47767 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-47767 being exploited in the wild.

**How severe is CVE-2026-47767?** Medium severity, with a CVSS score of 4, published 14 July 2026.

**Which products and versions are affected?** symfony/runtime (Packagist) ECOSYSTEM:introduced=5.4.46,fixed=5.4.52; symfony/symfony (Packagist) ECOSYSTEM:introduced=5.4.46,fixed=5.4.52; Symfony Runtime >= 5.4.46, < 5.4.52; >= 6.4.14, < 6.4.40; >= 7.1.7, < 7.4.12; >= 8.0.0-BETA1, < 8.0.12, >= 5.4.46, < 5.4.52; >= 6.4.14, < 6.4.40; >= 7.1.7, < 7.4.12; >= 8.0.0, < 8.0.12.

**Is there a fix for CVE-2026-47767?** Yes. symfony/runtime (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-2026-47767 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-47767?** Check whether you run symfony/runtime (Packagist), symfony/symfony (Packagist) or Symfony Runtime 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/runtime (Packagist): upgrade to 5.4.52 or later

  ```sh
  composer require symfony/runtime:^5.4.52
  ```

- symfony/symfony (Packagist): upgrade to 5.4.52 or later

  ```sh
  composer require symfony/symfony:^5.4.52
  ```


## Technical details

This vulnerability is a bypass of the fix for CVE-2024-50340. The original fix attempted to gate runtime 'argv' parsing by checking if the $_GET superglobal was empty. However, a discrepancy between how parse_str() and the web SAPI handle query strings allows an attacker to craft a request where $_GET remains empty while $_SERVER['argv'] still contains attacker-controlled flags. By injecting flags such as --env or --no-debug, an attacker can override critical application configurations (APP_ENV or APP_DEBUG). This is classified as an interpretation conflict (CWE-436). The issue is resolved by gating 'argv' parsing on $_SERVER['QUERY_STRING'] instead of $_GET.

## Affected products

- Symfony symfony/symfony >= 5.4.46, < 5.4.52; >= 6.4.14, < 6.4.40; >= 7.1.7, < 7.4.12; >= 8.0.0-BETA1, < 8.0.12
- Symfony symfony/runtime >= 5.4.46, < 5.4.52; >= 6.4.14, < 6.4.40; >= 7.1.7, < 7.4.12; >= 8.0.0-BETA1, < 8.0.12

## Identifiers

- CVE-2026-47767
- GHSA-fqc7-9xjw-jrh3

## Timeline

- 2026-07-14: disclosed
- 2026-07-14: advisory
- 2026-05-20: patched: Release date of fixed versions 5.4.52, 6.4.40, 7.4.12, and 8.0.12.

## References

- [https://github.com/symfony/symfony/commit/3228c3806ee511008bea19a95084d460b17e5d25](https://github.com/symfony/symfony/commit/3228c3806ee511008bea19a95084d460b17e5d25)
- [https://github.com/symfony/symfony/releases/tag/v5.4.52](https://github.com/symfony/symfony/releases/tag/v5.4.52)
- [https://github.com/symfony/symfony/releases/tag/v6.4.40](https://github.com/symfony/symfony/releases/tag/v6.4.40)
- [https://github.com/symfony/symfony/releases/tag/v7.4.12](https://github.com/symfony/symfony/releases/tag/v7.4.12)
- [https://github.com/symfony/symfony/releases/tag/v8.0.12](https://github.com/symfony/symfony/releases/tag/v8.0.12)
- [https://github.com/symfony/symfony/security/advisories/GHSA-fqc7-9xjw-jrh3](https://github.com/symfony/symfony/security/advisories/GHSA-fqc7-9xjw-jrh3)

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