Our Goals

When it comes to security issues, the Hyper project has one goal: to be tough and competent.

Security issues have real effects on real users, and it is the duty of library authors to protect users from those problems as much as possible. As a result, security is a paramount focus for our project, because if we fail and users are exploited or made vulnerable, we are to blame.

This attitude leads to the following guidelines for contributors and maintainers:

  • The default configuration of a Hyper project must be as secure as possible.
  • Any change that weakens the security of the default configuration of a Hyper project is to be resisted.
  • We will react swiftly to being notified of security vulnerabilities.
  • When notified of security vulnerabilities we will treat them all as serious incidents until otherwise determined: there is no such thing as a low severity security bug.
  • We will work with downstream maintainers to backport patches to all versions of the software that are affected by a vulnerability, regardless of whether that version is still actively supported by the core team.
  • It is better to break functioning-but-insecure code than it is to leave unaware users vulnerable.
  • If and when we break functioning-but-insecure code, we will provide error messages that adequately explain the problem.
  • Any insecure or less secure options made available in a Hyper project must cause warnings to be issued when used.

Known Vulnerabilities

This section of the page contains all known vulnerabilities in all libraries that make up the Python Hyper project. These vulnerabilities have all been reported to us via our vulnerability disclosure policy.

# Vulnerability Date Announced Library First Version Last Version CVE
2 HPACK Bomb 2016-08-04 HPACK 1.0.0 2.2.0 CVE-2016-6581
1 DoS via unlimited stream insertion 2016-08-04 Priority 1.0.0 1.1.1 CVE-2016-6580

Vulnerability Disclosure

If you think you have found a potential security vulnerability in a Hyper project, please email Lukasa directly. Do not file a public issue.

Lukasa’s PGP Key fingerprint is:

  • 90DC AE40 FEA7 4B14 9B70 662D F25F 2144 EEC1 373D

If English is not your first language, please try to describe the problem and its impact to the best of your ability. For greater detail, please use your native language and we will try our best to translate it using online services.

Please also include the code you used to find the problem and the shortest amount of code necessary to reproduce it.

Please do not disclose this to anyone else. We will retrieve a CVE identifier if necessary and give you full credit under whatever name or alias you provide. We will only request an identifier when we have a fix and can publish it in a release.

We will respect your privacy and will only publicize your involvement if you grant us permission.


This following information discusses the process the Hyper project follows in response to vulnerability disclosures. If you are disclosing a vulnerability, this section of the documentation lets you know how we will respond to your disclosure.


When you report an issue, one of the project members will respond to you within two days at the outside. In most cases responses will be faster, usually within 12 hours. This initial response will at the very least confirm receipt of the report.

If we were able to rapidly reproduce the issue, the initial response will also contain confirmation of the issue. If we are not, we will often ask for more information about the reproduction scenario.

Our goal is to have a fix for any vulnerability released within two weeks of the initial disclosure. This may potentially involve shipping an interim release that simply disables function while a more mature fix can be prepared, but will in the vast majority of cases mean shipping a complete release as soon as possible.

Throughout the fix process we will keep you up to speed with how the fix is progressing. Once the fix is prepared, we will notify you that we believe we have a fix. Often we will ask you to confirm the fix resolves the problem in your environment, especially if we are not confident of our reproduction scenario.

At this point, we will prepare for the release. We will obtain a CVE number if one is required, providing you with full credit for the discovery. We will also decide on a planned release date, and let you know when it is. This release date will always be on a weekday.

At this point we will reach out to our major downstream packagers to notify them of an impending security-related patch so they can make arrangements. In addition, these packagers will be provided with the intended patch ahead of time, to ensure that they are able to promptly release their downstream packages. Currently the list of people we actively contact ahead of a public release is empty. We will notify these individuals at least a week ahead of our planned release date to ensure that they have sufficient time to prepare. If you believe you should be on this list, please let one of the maintainers know at one of the email addresses at the top of this article.

On release day, we will push the patch to our public repository, along with an updated changelog that describes the issue and credits you. We will then issue a PyPI release containing the patch.

At this point, we will publicise the release. This will involve mails to mailing lists, Tweets, and all other communication mechanisms available to the core team.

We will also explicitly mention which commits contain the fix to make it easier for other distributors and users to easily patch their own versions of the project if upgrading is not an option. We will also work with downstream distributors to patch their software.