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This document explains how Symfony security issues are handled by the Symfony
core team (Symfony being the code hosted on the main
Reporting a Security Issue¶
If you think that you have found a security issue in Symfony, don’t use the bug tracker and don’t publish it publicly. Instead, all security issues must be sent to security [at] symfony.com. Emails sent to this address are forwarded to the Symfony core team private mailing-list.
For each report, we first try to confirm the vulnerability. When it is confirmed, the core team works on a solution following these steps:
- Send an acknowledgement to the reporter;
- Work on a patch;
- Get a CVE identifier from mitre.org;
- Write a security announcement for the official Symfony blog about the
vulnerability. This post should contain the following information:
- a title that always include the “Security release” string;
- a description of the vulnerability;
- the affected versions;
- the possible exploits;
- how to patch/upgrade/workaround affected applications;
- the CVE identifier;
- Send the patch and the announcement to the reporter for review;
- Apply the patch to all maintained versions of Symfony;
- Package new versions for all affected versions;
- Publish the post on the official Symfony blog (it must also be added to the “Security Advisories” category);
- Update the public security advisories database maintained by the
FriendsOfPHP organization and which is used by the
Releases that include security issues should not be done on Saturday or Sunday, except if the vulnerability has been publicly posted.
While we are working on a patch, please do not reveal the issue publicly.
The resolution takes anywhere between a couple of days to a month depending on its complexity and the coordination with the downstream projects (see next paragraph).
Collaborating with Downstream Open-Source Projects¶
As Symfony is used by many large Open-Source projects, we standardized the way the Symfony security team collaborates on security issues with downstream projects. The process works as follows:
- After the Symfony security team has acknowledged a security issue, it immediately sends an email to the downstream project security teams to inform them of the issue;
- The Symfony security team creates a private Git repository to ease the collaboration on the issue and access to this repository is given to the Symfony security team, to the Symfony contributors that are impacted by the issue, and to one representative of each downstream projects;
- All people with access to the private repository work on a solution to solve the issue via pull requests, code reviews, and comments;
- Once the fix is found, all involved projects collaborate to find the best date for a joint release (there is no guarantee that all releases will be at the same time but we will try hard to make them at about the same time). When the issue is not known to be exploited in the wild, a period of two weeks seems like a reasonable amount of time.
The list of downstream projects participating in this process is kept as small as possible in order to better manage the flow of confidential information prior to disclosure. As such, projects are included at the sole discretion of the Symfony security team.
As of today, the following projects have validated this process and are part of the downstream projects included in this process:
- Drupal (releases typically happen on Wednesdays)
You can check your Symfony application for known security vulnerabilities
security:check command (see How to Check for Known Security Vulnerabilities in Your Dependencies).
Check the Security Advisories blog category for a list of all security vulnerabilities that were fixed in Symfony releases, starting from Symfony 1.0.0.
This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.