CVE-2021-4034

CVE-2021-4034 is a high-severity vulnerability in Redhat Enterprise Linux Server Update Services For Sap Solutions with a CVSS 3.x base score of 7.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-06-27). The underlying weakness is classified as CWE-125.

Key facts

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.

Frequently asked questions

What is CVE-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.
How severe is CVE-2021-4034?
CVE-2021-4034 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-4034 being actively exploited?
Yes. CVE-2021-4034 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-06-27, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2021-4034?
CVE-2021-4034 primarily affects Redhat Enterprise Linux Server Update Services For Sap Solutions. In total, 54 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-4034?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2021-4034 have an EU (EUVD) identifier?
Yes. CVE-2021-4034 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33934. It is also flagged as exploited in the EUVD (since 2022-06-27).
When was CVE-2021-4034 published?
CVE-2021-4034 was published on 2022-01-28 and last updated on 2026-06-17.

References

Affected products (54)

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