High severity · published Jan 28, 2022
CVE-2021-4034
Red Hat Polkit Out-of-Bounds Read and Write Vulnerability
RansomwareIn wildKEV
7.8
CVSS
94.9%
EPSS
Yes
On KEV
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 vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)94.9% · higher than 100% of CVEs
Exploited in the wildYes
CISA KEVListed Jun 27, 2022
Federal remediation dueJul 18, 2022
Ransomware campaign useKnown
Affected products
Which versions
PO
Polkit · Polkit Project
before 121 · source: vendor, NVD, KEV
EL
Enterprise Linux · Redhat
8.0 · source: NVD
EL
EL
Enterprise Linux Server · Redhat
6.0; 7.0 · source: NVD