# CVE-2012-6431: Symfony Allows URI Restrictions Bypass Via Double-Encoded String

Source: https://junglewise.ai/threats/cve-2012-6431-symfony-allows-uri-restrictions-bypass-via-double-encoded-string  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-05-17  
License: CC BY 4.0 with a link back

CVE-2012-6431 · Severity: info · Published 2022-05-17

Symfony Allows URI Restrictions Bypass Via Double-Encoded String

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

## Quick answers

**Is CVE-2012-6431 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2012-6431 being exploited in the wild.

**How severe is CVE-2012-6431?** Informational severity, published 17 May 2022.

**Which products and versions are affected?** symfony/http-foundation (Packagist) ECOSYSTEM:introduced=2.0.0,fixed=2.0.19; symfony/routing (Packagist) ECOSYSTEM:introduced=2.0.0,fixed=2.0.19; symfony/security (Packagist) ECOSYSTEM:introduced=2.0.0,fixed=2.0.19; symfony/symfony (Packagist) ECOSYSTEM:introduced=2.0.0,fixed=2.0.19.

**Is there a fix for CVE-2012-6431?** Yes. symfony/http-foundation (Packagist): upgrade to 2.0.19 or later; symfony/routing (Packagist): upgrade to 2.0.19 or later; symfony/security (Packagist): upgrade to 2.0.19 or later; symfony/symfony (Packagist): upgrade to 2.0.19 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2012-6431?** Check whether you run symfony/http-foundation (Packagist), symfony/routing (Packagist), symfony/security (Packagist) or one of the others listed 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/http-foundation (Packagist): upgrade to 2.0.19 or later

  ```sh
  composer require symfony/http-foundation:^2.0.19
  ```

- symfony/routing (Packagist): upgrade to 2.0.19 or later

  ```sh
  composer require symfony/routing:^2.0.19
  ```

- symfony/security (Packagist): upgrade to 2.0.19 or later

  ```sh
  composer require symfony/security:^2.0.19
  ```

- symfony/symfony (Packagist): upgrade to 2.0.19 or later

  ```sh
  composer require symfony/symfony:^2.0.19
  ```


## Affected products

- symfony/http-foundation (Packagist) ECOSYSTEM:introduced=2.0.0,fixed=2.0.19
- symfony/routing (Packagist) ECOSYSTEM:introduced=2.0.0,fixed=2.0.19
- symfony/security (Packagist) ECOSYSTEM:introduced=2.0.0,fixed=2.0.19
- symfony/symfony (Packagist) ECOSYSTEM:introduced=2.0.0,fixed=2.0.19

## Identifiers

- CVE-2012-6431
- GHSA-83c3-qx27-2rwr

## Related threats

- [Symfony YAML stack exhaustion in inline lexer](https://junglewise.ai/threats/cve-2026-109413-in-symfony-yaml-prior-to-versions-5-4-54-6-4-45-7-4-18-and-8-1-6)
- [Symfony HTTP Foundation ReDoS in HeaderUtils::split()](https://junglewise.ai/threats/cve-2026-108082-symfony-is-a-php-framework-for-web-and-console-applications-and)
- [Symfony Routing improper dot-segment encoding in UrlGenerator](https://junglewise.ai/threats/cve-2026-48784-symfony-routing-improper-dot-segment-encoding-in-urlgenerator)
- [Symfony HtmlSanitizer XSS via incomplete URL attribute sanitization](https://junglewise.ai/threats/cve-2026-48761-symfony-htmlsanitizer-xss-via-incomplete-url-attribute)
- [Symfony HtmlSanitizer visual spoofing via percent-encoded BiDi characters](https://junglewise.ai/threats/cve-2026-48760-symfony-htmlsanitizer-visual-spoofing-via-percent-encoded-bidi)