.. _securitybugs:

Security bugs
=============

Linux kernel developers take security very seriously.  As such, we'd
like to know when a security bug is found so that it can be fixed and
disclosed as quickly as possible.  Please report security bugs to the
Linux kernel security team.

The security team and maintainers almost always require additional
information beyond what was initially provided in a report and rely on
active and efficient collaboration with the reporter to perform further
testing (e.g., verifying versions, configuration options, mitigations, or
patches). Before contacting the security team, the reporter must ensure
they are available to explain their findings, engage in discussions, and
run additional tests.  Reports where the reporter does not respond promptly
or cannot effectively discuss their findings may be abandoned if the
communication does not quickly improve.

As it is with any bug, the more information provided the easier it
will be to diagnose and fix.  Please review the procedure outlined in
'Documentation/admin-guide/reporting-issues.rst' if you are unclear about what
information is helpful.  Any exploit code is very helpful and will not
be released without consent from the reporter unless it has already been
made public.

The Linux kernel security team can be contacted by email at
<security@kernel.org>.  This is a private list of security officers
who will help verify the bug report and develop and release a fix.
If you already have a fix, please include it with your report, as
that can speed up the process considerably.  It is possible that the
security team will bring in extra help from area maintainers to
understand and fix the security vulnerability.

Please send **plain text** emails without attachments where possible.
It is much harder to have a context-quoted discussion about a complex
issue if all the details are hidden away in attachments.  Think of it like a
:doc:`regular patch submission <../process/submitting-patches>`
(even if you don't have a patch yet): describe the problem and impact, list
reproduction steps, and follow it with a proposed fix, all in plain text.
Markdown, HTML and RST formatted reports are particularly frowned upon since
they're quite hard to read for humans and encourage to use dedicated viewers,
sometimes online, which by definition is not acceptable for a confidential
security report.

Disclosure and embargoed information
------------------------------------

The security list is not a disclosure channel.  For that, see Coordination
below.

Once a robust fix has been developed, the release process starts.  Fixes
for publicly known bugs are released immediately.

Although our preference is to release fixes for publicly undisclosed bugs
as soon as they become available, this may be postponed at the request of
the reporter or an affected party for up to 7 calendar days from the start
of the release process, with an exceptional extension to 14 calendar days
if it is agreed that the criticality of the bug requires more time.  The
only valid reason for deferring the publication of a fix is to accommodate
the logistics of QA and large scale rollouts which require release
coordination.

While embargoed information may be shared with trusted individuals in
order to develop a fix, such information will not be published alongside
the fix or on any other disclosure channel without the permission of the
reporter.  This includes but is not limited to the original bug report
and followup discussions (if any), exploits, CVE information or the
identity of the reporter.

In other words our only interest is in getting bugs fixed.  All other
information submitted to the security list and any followup discussions
of the report are treated confidentially even after the embargo has been
lifted, in perpetuity.

Coordination with other groups
------------------------------

While the kernel security team solely focuses on getting bugs fixed,
other groups focus on fixing issues in distros and coordinating
disclosure between operating system vendors.  Coordination is usually
handled by the "linux-distros" mailing list and disclosure by the
public "oss-security" mailing list, both of which are closely related
and presented in the linux-distros wiki:
<https://oss-security.openwall.org/wiki/mailing-lists/distros>

Please note that the respective policies and rules are different since
the 3 lists pursue different goals.  Coordinating between the kernel
security team and other teams is difficult since for the kernel security
team occasional embargoes (as subject to a maximum allowed number of
days) start from the availability of a fix, while for "linux-distros"
they start from the initial post to the list regardless of the
availability of a fix.

As such, the kernel security team strongly recommends that as a reporter
of a potential security issue you DO NOT contact the "linux-distros"
mailing list UNTIL a fix is accepted by the affected code's maintainers
and you have read the distros wiki page above and you fully understand
the requirements that contacting "linux-distros" will impose on you and
the kernel community.  This also means that in general it doesn't make
sense to Cc: both lists at once, except maybe for coordination if and
while an accepted fix has not yet been merged.  In other words, until a
fix is accepted do not Cc: "linux-distros", and after it's merged do not
Cc: the kernel security team.

CVE assignment
--------------

The security team does not assign CVEs, nor do we require them for
reports or fixes, as this can needlessly complicate the process and may
delay the bug handling.  If a reporter wishes to have a CVE identifier
assigned for a confirmed issue, they can contact the :doc:`kernel CVE
assignment team<../process/cve>` to obtain one.

Non-disclosure agreements
-------------------------

The Linux kernel security team is not a formal body and therefore unable
to enter any non-disclosure agreements.
