Updated security.rst to expand on process

1 files changed, 63 insertions, 5 deletions

diff --git a/docs/security.rst b/docs/security.rst
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+++ b/docs/security.rst
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 Security
 ========
 
-We take the security of ``cryptography`` seriously. If you believe you've
-identified a security issue in it, please report it to
-``alex.gaynor@gmail.com``. Message may be encrypted with PGP using key
-fingerprint ``E27D 4AA0 1651 72CB C5D2  AF2B 125F 5C67 DFE9 4084`` (this public
-key is available from most commonly-used key servers).
+We take the security of ``cryptography`` seriously. The following are a set of
+policies we have adopted to ensure that security issues are addressed in a
+timely fashion.
+
+Reporting a security issue
+--------------------------
+
+We ask that you do not report security issues to our normal GitHub issue
+tracker.
+
+If you believe you've identified a security issue with ``cryptography``, please
+report it to ``alex.gaynor@gmail.com``. Message may be optionally be encrypted
+with PGP using  key fingerprint
+``E27D 4AA0 1651 72CB C5D2  AF2B 125F 5C67 DFE9 4084``
+(this public key is available from most commonly-used key servers).
 
 Once you've submitted an issue via email, you should receive an acknowledgment
 within 48 hours, and depending on the action to be taken, you may receive
 further follow-up emails.
+
+Supported Versions
+------------------
+
+At any given time, we will provide security support for the `master`_ branch
+as well as the 2 most recent releases.
+
+Disclosure Process
+------------------
+
+Our process for taking a security issue from private discussion to public
+disclosure involves multiple steps.
+
+Approximately one week before full public disclosure, we will send advance
+notification of the issue to a list of people and organizations, primarily
+composed of operating-system vendors and other distributors of
+``cryptography``.  This notification will consist of an email message,
+
+* A full description of the issue and the affected versions of
+  ``cryptography``.
+* The steps we will be taking to remedy the issue.
+* The patch(es), if any, that will be applied to ``cryptography``.
+* The date on which the ``cryptography`` team will apply these patches, issue
+  new releases and publicly disclose the issue.
+
+Simultaneously, the reporter of the issue will receive notification of the date
+on which we plan to take the issue public.
+
+On the day of disclosure, we will take the following steps:
+
+* Apply the relevant patch(es) to the ``cryptography`` codebase. The commit
+  messages for these patches will indicate that they are for security issues,
+  but will not describe the issue in any detail; instead, they will warn of
+  upcoming disclosure.
+* Issue the relevant release(s).
+* Post a notice to the cryptography mailing list that describes the issue in
+  detail, point to the new release and crediting the reporter of the issue.
+
+If a reported issue is believed to be particularly time-sensitive – due to a
+known exploit in the wild, for example – the time between advance notification
+and public disclosure may be shortened considerably.
+
+The list of people and organizations who receives advanced notification of
+security issues is not and will not be made public. This list generally
+consists of high profile downstream distributors and is entirely at the
+discretion of the ``cryptography`` team.
+
+.. _`master`: https://github.com/pyca/cryptography