# CVE-2026-48489: Symfony firewall bypass via failure_forward subrequest in security-http

Source: https://junglewise.ai/threats/cve-2026-48489-symfony-firewall-bypass-via-failure-forward-subrequest-in  
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-2026-48489 · Severity: high · CVSS 0 · Published 2026-07-14

A security flaw in the Symfony web framework allows unauthorized users to bypass security firewalls and access protected administrative pages or data. By sending a specially crafted login request that intentionally fails, an attacker can trick the system into displaying internal pages that should require a password. This could lead to the exposure of sensitive information, such as internal reports, user data, or administrative dashboards, even if the application is otherwise correctly configured.

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

## Quick answers

**Is CVE-2026-48489 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-48489 being exploited in the wild.

**How severe is CVE-2026-48489?** High severity, with a CVSS score of 0, published 14 July 2026.

**Which products and versions are affected?** symfony/security-http (Packagist) ECOSYSTEM:introduced=0,fixed=5.4.53; symfony/symfony (Packagist) ECOSYSTEM:introduced=0,fixed=5.4.53; Symfony Security HTTP < 5.4.53, >= 6.0.0-BETA1 < 6.4.41, >= 7.0.0-BETA1 < 7.4.13, >= 8.0.0-BETA1 < 8.0.13, < 5.4.53, >= 6.0.0, < 6.4.41, >= 7.0.0, < 7.4.13, >= 8.0.0, < 8.0.13.

**Is there a fix for CVE-2026-48489?** Yes. symfony/security-http (Packagist): upgrade to 5.4.53 or later; symfony/symfony (Packagist): upgrade to 5.4.53 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-48489 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-48489?** Check whether you run symfony/security-http (Packagist), symfony/symfony (Packagist) or Symfony Security HTTP 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/security-http (Packagist): upgrade to 5.4.53 or later

  ```sh
  composer require symfony/security-http:^5.4.53
  ```

- symfony/symfony (Packagist): upgrade to 5.4.53 or later

  ```sh
  composer require symfony/symfony:^5.4.53
  ```


## Technical details

An authorization bypass exists in Symfony's DefaultAuthenticationFailureHandler when the 'failure_forward' configuration is set to true. The handler incorrectly honors the '_failure_path' parameter provided in a login request, using it to dispatch an internal subrequest via HttpKernelInterface::SUB_REQUEST. Because Symfony's Firewall listener is designed to skip subrequests, the AccessListener (which enforces access_control rules) is bypassed. An unauthenticated attacker can exploit this by submitting a failing login request with a malicious '_failure_path' to access any GET route protected by the firewall. The issue is resolved in versions 5.4.53, 6.4.41, 7.4.13, and 8.0.13 by ensuring the handler only uses the developer-configured failure path.

## Affected products

- Symfony symfony/symfony < 5.4.53, >= 6.0.0-BETA1 < 6.4.41, >= 7.0.0-BETA1 < 7.4.13, >= 8.0.0-BETA1 < 8.0.13
- Symfony symfony/security-http < 5.4.53, >= 6.0.0-BETA1 < 6.4.41, >= 7.0.0-BETA1 < 7.4.13, >= 8.0.0-BETA1 < 8.0.13

## Identifiers

- CVE-2026-48489
- GHSA-6h46-9jf5-q59x

## Timeline

- 2026-05-27: patched: Security releases v5.4.53, v6.4.41, v7.4.13, and v8.0.13 published.
- 2026-07-14: disclosed: CVE-2026-48489 published.

## References

- [https://github.com/symfony/symfony/commit/c48a4276309e11aedeeb0ce3a89dfbf0b4fe04ff](https://github.com/symfony/symfony/commit/c48a4276309e11aedeeb0ce3a89dfbf0b4fe04ff)
- [https://github.com/symfony/symfony/releases/tag/v5.4.53](https://github.com/symfony/symfony/releases/tag/v5.4.53)
- [https://github.com/symfony/symfony/releases/tag/v6.4.41](https://github.com/symfony/symfony/releases/tag/v6.4.41)
- [https://github.com/symfony/symfony/releases/tag/v7.4.13](https://github.com/symfony/symfony/releases/tag/v7.4.13)
- [https://github.com/symfony/symfony/security/advisories/GHSA-6h46-9jf5-q59x](https://github.com/symfony/symfony/security/advisories/GHSA-6h46-9jf5-q59x)

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