38 Dealing with Vulnerability Reports

The Yocto Project and OpenEmbedded are open-source, community-based projects used in numerous products. They assemble multiple other open-source projects, and need to handle security issues and practices both internal (in the code maintained by both projects), and external (maintained by other projects and organizations).

This manual assembles security-related information concerning the whole ecosystem. It includes information on reporting a potential security issue, the operation of the YP Security team and how to contribute in the related code. It is written to be useful for both security researchers and YP developers.

38.1 How to report a potential security vulnerability?

If you would like to report a public issue (for example, one with a released CVE number), please report it using the Security Bugzilla.

If you are dealing with a not-yet-released issue, or an urgent one, please send a message to security AT yoctoproject DOT org, including as many details as possible: the layer or software module affected, the recipe and its version, and any example code, if available. This mailing list is monitored by the Yocto Project Security team.

For each layer, you might also look for specific instructions (if any) for reporting potential security issues in the specific SECURITY.md file at the root of the repository. Instructions on how and where submit a patch are usually available in README.md. If this is your first patch to the Yocto Project/OpenEmbedded, you might want to have a look into the Contributor’s Manual section “Preparing Changes for Submission”.

38.1.1 Branches maintained with security fixes

See the Release process documentation for details regarding the policies and maintenance of stable branches.

The Releases page contains a list of all releases of the Yocto Project. Versions in gray are no longer actively maintained with security patches, but well-tested patches may still be accepted for them for significant issues.

38.1.3 What you should do if you find a security vulnerability

If you find a security flaw: a crash, an information leakage, or anything that can have a security impact if exploited in any Open Source software built or used by the Yocto Project, please report this to the Yocto Project Security Team. If you prefer to contact the upstream project directly, please send a copy to the security team at the Yocto Project as well. If you believe this is highly sensitive information, please report the vulnerability in a secure way, i.e. encrypt the email and send it to the private list. This ensures that the exploit is not leaked and exploited before a response/fix has been generated.

38.2 Security team

The Yocto Project/OpenEmbedded security team coordinates the work on security subjects in the project. All general discussion takes place publicly. The Security Team only uses confidential communication tools to deal with private vulnerability reports before they are released.

38.2.1 Security team appointment

The Yocto Project Security Team consists of at least three members. When new members are needed, the Yocto Project Technical Steering Committee (YP TSC) asks for nominations by public channels including a nomination deadline. Self-nominations are possible. When the limit time is reached, the YP TSC posts the list of candidates for the comments of project participants and developers. Comments may be sent publicly or privately to the YP and OE TSCs. The candidates are approved by both YP TSC and OpenEmbedded Technical Steering Committee (OE TSC) and the final list of the team members is announced publicly. The aim is to have people representing technical leadership, security knowledge and infrastructure present with enough people to provide backup/coverage but keep the notification list small enough to minimize information risk and maintain trust.

YP Security Team members may resign at any time.

38.2.2 Security Team Operations

The work of the Security Team might require high confidentiality. Team members are individuals selected by merit and do not represent the companies they work for. They do not share information about confidential issues outside of the team and do not hint about ongoing embargoes.

Team members can bring in domain experts as needed. Those people should be added to individual issues only and adhere to the same standards as the YP Security Team.

The YP security team organizes its meetings and communication as needed.

When the YP Security team receives a report about a potential security vulnerability, they quickly analyze and notify the reporter of the result. They might also request more information.

If the issue is confirmed and affects the code maintained by the YP, they confidentially notify maintainers of that code and work with them to prepare a fix.

If the issue is confirmed and affects an upstream project, the YP security team notifies the project. Usually, the upstream project analyzes the problem again. If they deem it a real security problem in their software, they develop and release a fix following their security policy. They may want to include the original reporter in the loop. There is also sometimes some coordination for handling patches, backporting patches etc, or just understanding the problem or what caused it.

When the fix is publicly available, the YP security team member or the package maintainer sends patches against the YP code base, following usual procedures, including public code review.

38.2.3 What Yocto Security Team does when it receives a security vulnerability

The YP Security Team team performs a quick analysis and would usually report the flaw to the upstream project. Normally the upstream project analyzes the problem. If they deem it a real security problem in their software, they develop and release a fix following their own security policy. They may want to include the original reporter in the loop. There is also sometimes some coordination for handling patches, backporting patches etc, or just understanding the problem or what caused it.

The security policy of the upstream project might include a notification to Linux distributions or other important downstream projects in advance to discuss coordinated disclosure. These mailing lists are normally non-public.

When the upstream project releases a version with the fix, they are responsible for contacting Mitre to get a CVE number assigned and the CVE record published.

38.2.4 If an upstream project does not respond quickly

If an upstream project does not fix the problem in a reasonable time, the Yocto’s Security Team will contact other interested parties (usually other distributions) in the community and together try to solve the vulnerability as quickly as possible.

The Yocto Project Security team adheres to the 90 days disclosure policy by default. An increase of the embargo time is possible when necessary.

38.2.5 Current Security Team members

For secure communications, please send your messages encrypted using the GPG keys. Remember, message headers are not encrypted so do not include sensitive information in the subject line.