Description
A local privilege escalation vulnerability was found on polkit's pkexec utility. The pkexec application is a setuid tool designed to allow unprivileged users to run commands as privileged users according predefined policies. The current version of pkexec doesn't handle the calling parameters count correctly and ends trying to execute environment variables as commands. An attacker can leverage this by crafting environment variables in such a way it'll induce pkexec to execute arbitrary code. When successfully executed the attack can cause a local privilege escalation given unprivileged users administrative rights on the target machine.
CVSS breakdown
CVSS 3.1
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected products
- Canonical / Ubuntu Linux20.04 – 20.04
- Canonical / Ubuntu Linux18.04 – 18.04
- Canonical / Ubuntu Linux14.04 – 14.04
- Canonical / Ubuntu Linux16.04 – 16.04
- Canonical / Ubuntu Linux21.10 – 21.10
- oracle / http_server12.2.1.3.0 – 12.2.1.3.0
- oracle / http_server12.2.1.4.0 – 12.2.1.4.0
- oracle / zfs_storage_appliance_kit8.8 – 8.8
- polkit_project / polkit121
- RedHat / enterprise_linux8.0 – 8.0
- RedHat / enterprise_linux_desktop7.0 – 7.0
- RedHat / enterprise_linux_eus8.2 – 8.2
- RedHat / enterprise_linux_for_ibm_z_systems7.0 – 7.0
- RedHat / enterprise_linux_for_ibm_z_systems8.0 – 8.0
- RedHat / enterprise_linux_for_ibm_z_systems_eus8.2 – 8.2
- RedHat / enterprise_linux_for_ibm_z_systems_eus8.4 – 8.4
- RedHat / enterprise_linux_for_power_big_endian7.0 – 7.0
- RedHat / enterprise_linux_for_power_little_endian8.0 – 8.0
- RedHat / enterprise_linux_for_power_little_endian7.0 – 7.0
- RedHat / enterprise_linux_for_power_little_endian_eus8.1 – 8.1
- RedHat / enterprise_linux_for_power_little_endian_eus8.4 – 8.4
- RedHat / enterprise_linux_for_power_little_endian_eus8.2 – 8.2
- RedHat / enterprise_linux_for_scientific_computing7.0 – 7.0
- RedHat / enterprise_linux_server7.0 – 7.0
- RedHat / enterprise_linux_server6.0 – 6.0
- RedHat / enterprise_linux_server_aus7.3 – 7.3
- RedHat / enterprise_linux_server_aus7.4 – 7.4
- RedHat / enterprise_linux_server_aus7.6 – 7.6
- RedHat / enterprise_linux_server_aus7.7 – 7.7
- RedHat / enterprise_linux_server_aus8.2 – 8.2
- RedHat / enterprise_linux_server_aus8.4 – 8.4
- RedHat / enterprise_linux_server_eus8.4 – 8.4
- RedHat / enterprise_linux_server_tus7.7 – 7.7
- RedHat / enterprise_linux_server_tus7.6 – 7.6
- RedHat / enterprise_linux_server_tus8.2 – 8.2
- RedHat / enterprise_linux_server_tus8.4 – 8.4
- RedHat / enterprise_linux_server_update_services_for_sap_solutions8.1 – 8.1
- RedHat / enterprise_linux_server_update_services_for_sap_solutions8.4 – 8.4
- RedHat / enterprise_linux_server_update_services_for_sap_solutions8.2 – 8.2
- RedHat / enterprise_linux_server_update_services_for_sap_solutions7.6 – 7.6
- RedHat / enterprise_linux_server_update_services_for_sap_solutions7.7 – 7.7
- RedHat / enterprise_linux_workstation7.0 – 7.0
- Siemens / scalance_lpe9403_firmware2.0
- Siemens / SINUMERIK Edge3.3.0
- starwindsoftware / command_center1.0 – 1.0
- starwindsoftware / starwind_virtual_sanv8 – v8
- SUSE / enterprise_storage7.0 – 7.0
- SUSE / linux_enterprise_desktop15 – 15
- SUSE / linux_enterprise_high_performance_computing15.0 – 15.0
- SUSE / linux_enterprise_server15 – 15
- SUSE / linux_enterprise_server15 – 15
- SUSE / linux_enterprise_workstation_extension12 – 12
- SUSE / manager_proxy4.1 – 4.1
- SUSE / manager_server4.1 – 4.1
Exploits & proofs of concept
- exploit-dbPolicyKit-1 0.105-31 - Privilege Escalationby Lance Biggerstaff
References
- VENDOR_ADVISORYhttps://access.redhat.com/security/vulnerabilities/RHSB-2022-001
- MISChttps://www.qualys.com/2022/01/25/cve-2021-4034/pwnkit.txt
- MISChttps://bugzilla.redhat.com/show_bug.cgi?id=2025869
- MISChttps://gitlab.freedesktop.org/polkit/polkit/-/commit/a2bf5c9c83b6ae46cbd5c779d3055bff81ded683
- VENDOR_ADVISORYhttps://www.oracle.com/security-alerts/cpuapr2022.html
- EXPLOIThttp://packetstormsecurity.com/files/166196/Polkit-pkexec-Local-Privilege-Escalation.html
- EXPLOIThttp://packetstormsecurity.com/files/166200/Polkit-pkexec-Privilege-Escalation.html
- MISChttps://www.suse.com/support/kb/doc/?id=000020564
- MISChttps://cert-portal.siemens.com/productcert/pdf/ssa-330556.pdf
- MISChttps://www.starwindsoftware.com/security/sw-20220818-0001/
- MISChttps://www.secpod.com/blog/local-privilege-escalation-vulnerability-in-major-linux-distributions-cve-2021-4034/
Updated 18m ago · 8 sources