Bug 751556 (CVE-2020-15238) – <net-wireless/blueman-2.1.4: local privilege escalation in org.blueman.Mechanism D-Bus interface (CVE-2020-15238)

• Product: Gentoo Security
• Status: RESOLVED FIXED

[Description filip ambroz 2020-10-28 08:45:51 UTC]

Impact
------

The DhcpClient method of the D-Bus interface to blueman-mechanism is prone to an argument injection vulnerability.

The impact highly depends on the system configuration.

If Polkit-1 is disabled and for versions lower than 2.0.6, any local user can possibly exploit this. If Polkit-1 is enabled for version 2.0.6 and later, a possible attacker needs to be allowed to use the org.blueman.dhcp.client action. That is limited to users in the wheel group in the shipped rules file that do have the privileges anyway.

On systems with ISC DHCP client (dhclient), attackers can pass arguments to ip link with the interface name that can e.g. be used to bring down an interface or add an arbitrary XDP/BPF program.

On systems with dhcpcd and without ISC DHCP client, attackers can even run arbitrary scripts by passing -c/path/to/script as an interface name.


Patches
-------

Patches are included in 2.1.4 and master that change the DhcpClient D-Bus method(s) to accept BlueZ network object paths instead of network interface names. A backport to 2.0(.8) is also available.


Workarounds
-----------

Make sure that Polkit-1-support is enabled and limit privileges for the org.blueman.dhcp.client action to users that are able to run arbitrary commands as root anyway in /usr/share/polkit-1/rules.d/blueman.rules.


Links
-----
https://github.com/blueman-project/blueman/releases/tag/2.1.4
https://nvd.nist.gov/vuln/detail/CVE-2020-15238
https://osint.geekcq.com/2020/10/27/cve-2020-15238/
https://bugs.launchpad.net/ubuntu/+source/blueman/+bug/1897287



Reproducible: Always

[Comment 1 Thomas Deutschmann (RETIRED) 2020-10-28 14:33:41 UTC]

x86 stable

[Comment 2 Sam James 2020-10-28 16:45:46 UTC]

arm done

[Comment 3 Sam James 2020-10-29 01:22:45 UTC]

arm64 done

[Comment 4 Sergei Trofimovich (RETIRED) 2020-10-31 21:01:31 UTC]

ppc/ppc64 stable

[Comment 5 Sam James 2020-11-01 11:11:50 UTC]

arm64 done

[Comment 6 Sam James 2020-11-01 11:12:53 UTC]

arm done

[Comment 7 Sam James 2020-11-01 14:21:38 UTC]

amd64 done

all arches done

[Comment 8 Larry the Git Cow 2020-11-01 14:34:37 UTC]

The bug has been referenced in the following commit(s):

https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=5e7942ca7449b477f3581a1ac4c8408db1c95746

commit 5e7942ca7449b477f3581a1ac4c8408db1c95746
Author:     Michał Górny <[e-mail]>
AuthorDate: 2020-11-01 14:31:40 +0000
Commit:     Michał Górny <[e-mail]>
CommitDate: 2020-11-01 14:34:33 +0000

    net-wireless/blueman: Remove old
    
    Bug: https://bugs.gentoo.org/751556
    Signed-off-by: Michał Górny <[e-mail]>

 net-wireless/blueman/Manifest             |   1 -
 net-wireless/blueman/blueman-2.1.3.ebuild | 131 ------------------------------
 2 files changed, 132 deletions(-)

[Comment 9 GLSAMaker/CVETool Bot 2020-11-11 03:50:13 UTC]

This issue was resolved and addressed in
 GLSA 202011-11 at https://security.gentoo.org/glsa/202011-11
by GLSA coordinator Sam James (sam_c).