Actively exploited · CISA KEV · NVD published 2022-01-28
Actively exploitedCVE-2021-4034
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.
- First PoC
- 1546 days →Metasploit
- 178 days →First cited attacker
Signals
- Exploited in the wild
- Yesadded 2022-06-27 · due 2022-07-18 · known ransomware use. An observation, not a forecast.
- EPSS · 30-day forecast
- 95%Chance of exploitation in the next 30 days, 100th percentile of all CVEs. A forecast; KEV outranks it.
- CVSS · NVD · HIGH
- 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Internet exposure
- not stated by sourcesNo exposure census on this CVE's dispatches.
Exploits
2 known · links onlyMetasploit1
A bug exists in the polkit pkexec binary in how it processes arguments. If the binary is provided with no arguments, it will continue to process environment variables as argument variables, but without any security checking. By using the execve call we can specify a null argument list and populate the proper environment variables. This exploit is architecture independent.
ruby · seen 2026-10-18
Exploit-DB1
created 2022-01-27
On the wire
0 dispatchesNo dispatch on our wire has named this CVE yet.
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