Buffer overflow in Oracle HTTP Server

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.

Vulnerability class: Buffer Overflow

EPSS: 0.949 (99.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: .

Required action: Apply updates per vendor instructions.

Known ransomware campaign use: yes.

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-4034?
CVE-2021-4034 is a high-severity vulnerability in Oracle HTTP Server, classified under Out-of-bounds Write. CVSS score: 7.8/10. Published 2022-01-28.
How severe is CVE-2021-4034?
High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2021-4034 known to be exploited?
Yes. CVE-2021-4034 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-06-27), indicating it is being actively exploited. 598 public proof-of-concept repositories are indexed.