CVE-2021-4034
Red Hat Polkit Out-of-Bounds Read and Write Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.
Required action
Apply updates per vendor instructions.
CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2021-4034
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.
Severity
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HAffected Products
| Vendor | Product | Affected versions |
|---|---|---|
| - | polkit | all |
References
12 Links- https://access.redhat.com/security/vulnerabilities/RHSB-2022-001
- https://www.qualys.com/2022/01/25/cve-2021-4034/pwnkit.txt
- https://bugzilla.redhat.com/show_bug.cgi?id=2025869
- https://gitlab.freedesktop.org/polkit/polkit/-/commit/a2bf5c9c83b6ae46cbd5c779d3055bff81ded683
- https://www.oracle.com/security-alerts/cpuapr2022.html
- http://packetstormsecurity.com/files/166196/Polkit-pkexec-Local-Privilege-Escalation.html
- http://packetstormsecurity.com/files/166200/Polkit-pkexec-Privilege-Escalation.html
- https://www.suse.com/support/kb/doc/?id=000020564
- https://cert-portal.siemens.com/productcert/pdf/ssa-330556.pdf
- https://www.starwindsoftware.com/security/sw-20220818-0001/
- https://www.secpod.com/blog/local-privilege-escalation-vulnerability-in-major-linux-distributions-cve-2021-4034/
- https://www.vicarius.io/vsociety/posts/pwnkit-pkexec-lpe-cve-2021-4034
Record Details
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