CVE-2015-2309
All 2.0.X, 2.1.X, 2.2.X, 2.3.X, 2.4.X, 2.5.X, and 2.6.X versions of the Symfony HttpFoundation component are affected by this security issue.
This issue has been fixed in Symfony 2.3.27, 2.5.11, and 2.6.6. Note that no fixes are provided for Symfony 2.0, 2.1, 2.2, and 2.4 as they are not maintained anymore.
Description
The Symfony\Component\HttpFoundation\Request class provides a mechanism that ensures it does not trust HTTP header values coming from a "non-trusted" client. Unfortunately, it assumes that the remote address is always a trusted client if at least one trusted proxy is involved in the request; this allows a man-in-the-middle attack between the latest trusted proxy and the web server.
The following methods are impacted: getPort(), isSecure(), and getHost(), and getClientIps().
Resolution
All impacted methods now check that the remote address is trusted, which fixes the issue.
The patch for this issue is available here.
| Software | From | Fixed in |
|---|---|---|
symfony / http-foundation
|
2.0.0 | 2.3.27 |
|
symfony / http-foundation
|
2.4.0 | 2.5.11 |
|
symfony / http-foundation
|
2.6.0 | 2.6.6 |
|
symfony / symfony
|
2.0.0 | 2.3.27 |
|
symfony / symfony
|
2.4.0 | 2.5.11 |
|
symfony / symfony
|
2.6.0 | 2.6.6 |
- https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/http-foundation/CVE-2015-2309.yaml
- https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2015-2309.yaml
- https://github.com/symfony/symfony/commit/6c73f0ce9302a0091bbfbb96f317e400ce16ef84
- https://github.com/symfony/symfony/pull/14166
- https://symfony.com/cve-2015-2309
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A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.
A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.
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