Bug 1389433 (CVE-2016-9604) - CVE-2016-9604 kernel: security: The built-in keyrings for security tokens can be joined as a session and then modified by the root user
Summary: CVE-2016-9604 kernel: security: The built-in keyrings for security tokens can...
Status: CLOSED ERRATA
Alias: CVE-2016-9604
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
low
low
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
URL:
Whiteboard: impact=low,public=20170418,reported=2...
Keywords: Security
Depends On: 1389309 1440220 1440223 1440224 1446566 1446569
Blocks: 1389436
TreeView+ depends on / blocked
 
Reported: 2016-10-27 14:59 UTC by Adam Mariš
Modified: 2019-06-11 11:13 UTC (History)
22 users (show)

(edit)
It was discovered that root can gain direct access to an internal keyring, such as '.dns_resolver' in RHEL-7 or '.builtin_trusted_keys' upstream, by joining it as its session keyring. This allows root to bypass module signature verification by adding a new public key of its own devising to the keyring.
Clone Of:
(edit)
Last Closed: 2019-06-08 03:01:26 UTC


Attachments (Terms of Use)


External Trackers
Tracker ID Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2017:1842 normal SHIPPED_LIVE Important: kernel security, bug fix, and enhancement update 2017-08-01 18:22:09 UTC
Red Hat Product Errata RHSA-2017:2077 normal SHIPPED_LIVE Important: kernel-rt security, bug fix, and enhancement update 2017-08-01 18:13:37 UTC
Red Hat Product Errata RHSA-2017:2669 normal SHIPPED_LIVE Important: kernel-rt security and bug fix update 2017-09-07 00:36:52 UTC

Description Adam Mariš 2016-10-27 14:59:22 UTC
It was found that it is possible for root to gain direct access to an internal keyring, such as '.dns_resolver' in RHEL-7 or '.builtin_trusted_keys' upstream, by joining it as its session keyring. This allows root to bypass module signature verification by adding a new public key of its own devising to the keyring.

References:

https://bugzilla.novell.com/show_bug.cgi?id=1035576

http://people.canonical.com/~ubuntu-security/cve/2016/CVE-2016-9604.html

Upstream patch:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ee8f844e3c5a73b999edf733df1c529d6503ec2f

Comment 1 Adam Mariš 2016-10-27 14:59:36 UTC
Acknowledgments:

Name: David Howells (Red Hat)

Comment 5 Vladis Dronov 2017-04-07 15:04:11 UTC
Statement:

This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5 as the code with the flaw is not present in this product.

This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 6, 7 and MRG-2. Future Linux kernel updates for the respective releases might address this issue.

Comment 9 Vladis Dronov 2017-04-28 11:06:35 UTC
Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1446566]

Comment 11 errata-xmlrpc 2017-08-01 19:09:56 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2017:2077 https://access.redhat.com/errata/RHSA-2017:2077

Comment 12 errata-xmlrpc 2017-08-02 07:49:59 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2017:1842 https://access.redhat.com/errata/RHSA-2017:1842

Comment 13 errata-xmlrpc 2017-09-06 20:38:18 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise MRG 2

Via RHSA-2017:2669 https://access.redhat.com/errata/RHSA-2017:2669


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