Bug 1525762 (CVE-2017-17449)

Summary: CVE-2017-17449 kernel: Missing namespace check in net/netlink/af_netlink.c allows for network monitors to observe systemwide activity
Product: [Other] Security Response Reporter: Sam Fowler <sfowler>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: airlied, ajax, aquini, bhu, blc, bskeggs, dhoward, dominik.mierzejewski, ewk, fhrbata, hdegoede, hkrzesin, hwkernel-mgr, ichavero, itamar, jarodwilson, jeremy, jforbes, jglisse, jkacur, john.j5live, jonathan, josef, jwboyer, kernel-maint, kernel-mgr, labbott, lgoncalv, linville, mchehab, mjg59, mlangsdo, nmurray, plougher, rvrbovsk, skozina, slawomir, steved, tomichi, vdronov, williams
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
The __netlink_deliver_tap_skb function in net/netlink/af_netlink.c in the Linux kernel, through 4.14.4, does not restrict observations of Netlink messages to a single net namespace, when CONFIG_NLMON is enabled. This allows local users to obtain sensitive information by leveraging the CAP_NET_ADMIN capability to sniff an nlmon interface for all Netlink activity on the system.
Story Points: ---
Clone Of: Environment:
Last Closed: 2019-06-08 03:34:14 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 1525763, 1538733, 1538734, 1538735, 1538736, 1538737, 1538738, 1538739    
Bug Blocks: 1525773    

Description Sam Fowler 2017-12-14 01:47:17 UTC
The __netlink_deliver_tap_skb function in net/netlink/af_netlink.c in the Linux kernel through 4.14.4, when CONFIG_NLMON is enabled, does not restrict observations of Netlink messages to a single net namespace, which allows local users to obtain sensitive information by leveraging the CAP_NET_ADMIN capability to sniff an nlmon interface for all Netlink activity on the system.

References:

https://lkml.org/lkml/2017/12/5/950

http://patchwork.ozlabs.org/patch/845319/

An upstream patch:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=93c647643b48f0131f02e45da3bd367d80443291

Comment 1 Sam Fowler 2017-12-14 01:48:23 UTC
Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1525763]

Comment 5 Vladis Dronov 2018-01-25 17:18:35 UTC
Statement:

This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5 and 6, as a code with the flaw is not present or is not built in the products listed.

This issue affects the versions of the Linux kernel as shipped with Red Hat Enterprise Linux 7, its real-time kernel, Red Hat Enterprise MRG 2, Red Hat Enterprise Linux 7 for ARM 64 and Red Hat Enterprise Linux 7 for Power 9 LE. Future Linux kernel updates for the respective releases may address this issue.

Comment 6 Vladis Dronov 2018-01-25 17:19:11 UTC
What is Red Hat Enterprise Linux 7 for ARM 64,
        Red Hat Enterprise Linux 7 for Power 9 LE

The kernel package as shipped with Red Hat Enterprise Linux 7 for ARM 64 and Red Hat Enterprise Linux 7 for Power 9 LE is an updated kernel intended to support new architectures not available at the time of Red Hat Enterprise Linux 7 original shipping. The new kernel version is based on an upstream Linux kernel version 4.11. The offering is distributed with other updated packages, but most of the userspace is the standard Red Hat Enterprise Linux 7 Server RPM files.

For more information please refer to:

https://access.redhat.com/articles/3158541
https://access.redhat.com/articles/3158511

Comment 9 errata-xmlrpc 2018-04-10 05:10:25 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2018:0654 https://access.redhat.com/errata/RHSA-2018:0654

Comment 10 errata-xmlrpc 2018-04-10 08:15:24 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2018:0676 https://access.redhat.com/errata/RHSA-2018:0676

Comment 11 errata-xmlrpc 2018-04-10 09:39:10 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2018:1062 https://access.redhat.com/errata/RHSA-2018:1062

Comment 12 errata-xmlrpc 2018-04-17 15:31:57 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise MRG 2

Via RHSA-2018:1170 https://access.redhat.com/errata/RHSA-2018:1170

Comment 13 errata-xmlrpc 2018-04-17 16:22:38 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7.4 Extended Update Support

Via RHSA-2018:1130 https://access.redhat.com/errata/RHSA-2018:1130