CVE-2014-5244 is a high-severity (CVSS 7.5) vulnerability in symfony/http-foundation. A fix is available for symfony/http-foundation — see the affected versions and patch details below.
Symfony vulnerable to denial of service via a malicious HTTP Host header
Real-World Exposure
symfony/http-foundation🐘symfony/http-foundation🐘symfony/http-foundation🐘symfony/symfony🐘symfony/symfony🐘symfony/symfonyReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
All 2.0.X, 2.1.X, 2.2.X, 2.3.X, 2.4.X, and 2.5.X versions of the Symfony HttpFoundation component are affected by this security issue.
This issue has been fixed in Symfony 2.3.19, 2.4.9, and 2.5.4. Note that no fixes are provided for Symfony 2.0, 2.1, and 2.2 as they are not maintained anymore.
Description
When an arbitrarily long hostname is sent by a client, its parsing in Request::getHost() can lead to a DoS attack, due to the way we validate the hostname via a regular expression.
Resolution The regular expression used to parse and validate the hostname from the HTTP request has been modified to avoid too much sensitivity to the submitted value length.
The patch for this issue is available here: https://github.com/symfony/symfony/pull/11828
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | symfony/http-foundation | ≥ 2.0.0&&< 2.3.19 | 2.3.19composer require symfony/http-foundation:^2.3.19 |
| 🐘Packagist | symfony/http-foundation | ≥ 2.4.0&&< 2.4.9 | 2.4.9composer require symfony/http-foundation:^2.4.9 |
| 🐘Packagist | symfony/http-foundation | ≥ 2.5.0&&< 2.5.4 | 2.5.4composer require symfony/http-foundation:^2.5.4 |
| 🐘Packagist | symfony/symfony | ≥ 2.0.0&&< 2.3.19 | 2.3.19composer require symfony/symfony:^2.3.19 |
| 🐘Packagist | symfony/symfony | ≥ 2.4.0&&< 2.4.9 | 2.4.9composer require symfony/symfony:^2.4.9 |
| 🐘Packagist | symfony/symfony | ≥ 2.5.0&&< 2.5.4 | 2.5.4composer require symfony/symfony:^2.5.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for symfony/http-foundation, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update symfony/http-foundation to 2.3.19 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2014-5244 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
Frequently Asked Questions
Is CVE-2014-5244 in your dependencies?
Find it across Packagist, including transitive dependencies.