{"id":"CVE-2021-4034","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-4034","generatedAt":"2026-10-31T12:56:27.955Z","title":"Red Hat Polkit Out-of-Bounds Read and Write Vulnerability","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.","published":"2022-01-28T20:15:12.000Z","lastModified":"2026-08-15T04:17:58.000Z","status":"Analyzed","sourceIdentifier":"secalert@redhat.com","cvss":{"version":"3.1","score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-787","CWE-125"],"affected":["polkit project/polkit","redhat/enterprise linux server update services for sap solutions","redhat/enterprise linux","redhat/enterprise linux desktop","redhat/enterprise linux eus","redhat/enterprise linux for ibm z systems","redhat/enterprise linux for ibm z systems eus","redhat/enterprise linux for power big endian","redhat/enterprise linux for power little endian","redhat/enterprise linux for power little endian eus","redhat/enterprise linux for scientific computing","redhat/enterprise linux server","redhat/enterprise linux server aus","redhat/enterprise linux server eus","redhat/enterprise linux server tus","redhat/enterprise linux workstation","canonical/ubuntu linux","suse/enterprise storage","suse/linux enterprise high performance computing","suse/manager proxy","suse/manager server","suse/linux enterprise desktop","suse/linux enterprise server","suse/linux enterprise workstation extension","oracle/http server","oracle/zfs storage appliance kit","siemens/sinumerik edge","siemens/scalance lpe9403 firmware","starwindsoftware/command center","starwindsoftware/starwind virtual san"],"epss":{"score":0.94921,"percentile":0.9986,"date":"2026-10-30","history":[]},"kev":{"listed":true,"dateAdded":"2022-06-27","dueDate":"2022-07-18","knownRansomwareCampaignUse":"Known","notes":"Apply updates per vendor instructions.\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-4034"},"exploits":{"count":1,"verified":false,"firstPublished":"2022-01-27","source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[{"edbId":50689,"kind":"exploit","title":"PolicyKit-1 0.105-31 - Privilege Escalation","url":"https://www.exploit-db.com/exploits/50689","sourceUrl":"https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/linux/local/50689.txt","file":"exploits/linux/local/50689.txt","published":"2022-01-27","added":"2022-01-27","updated":"2022-01-27","author":"Lance Biggerstaff","type":"local","platform":"linux","port":null,"verified":false,"codes":["CVE-2021-4034"],"tags":null,"aliases":null,"applicationUrl":null,"screenshotUrl":null,"referenceUrl":null}]},"verdict":{"level":"urgent","text":"Known to be exploited in the wild (CISA KEV, CISA remediation deadline 18 July 2022). Treat as an emergency change: patch or isolate now, then hunt for prior compromise."},"changes":[],"references":[{"url":"http://packetstormsecurity.com/files/166196/Polkit-pkexec-Local-Privilege-Escalation.html","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"secalert@redhat.com"},{"url":"http://packetstormsecurity.com/files/166200/Polkit-pkexec-Privilege-Escalation.html","tags":["Third Party Advisory","VDB Entry"],"source":"secalert@redhat.com"},{"url":"https://access.redhat.com/security/vulnerabilities/RHSB-2022-001","tags":["Mitigation","Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2025869","tags":["Issue Tracking","Patch"],"source":"secalert@redhat.com"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-330556.pdf","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://gitlab.freedesktop.org/polkit/polkit/-/commit/a2bf5c9c83b6ae46cbd5c779d3055bff81ded683","tags":["Patch"],"source":"secalert@redhat.com"},{"url":"https://www.oracle.com/security-alerts/cpuapr2022.html","tags":["Patch","Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://www.qualys.com/2022/01/25/cve-2021-4034/pwnkit.txt","tags":["Exploit","Mitigation","Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://www.secpod.com/blog/local-privilege-escalation-vulnerability-in-major-linux-distributions-cve-2021-4034/","tags":["Exploit","Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://www.starwindsoftware.com/security/sw-20220818-0001/","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"https://www.suse.com/support/kb/doc/?id=000020564","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://packetstormsecurity.com/files/166196/Polkit-pkexec-Local-Privilege-Escalation.html","tags":["Exploit","Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://packetstormsecurity.com/files/166200/Polkit-pkexec-Privilege-Escalation.html","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/security/vulnerabilities/RHSB-2022-001","tags":["Mitigation","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2025869","tags":["Issue Tracking","Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-330556.pdf","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://gitlab.freedesktop.org/polkit/polkit/-/commit/a2bf5c9c83b6ae46cbd5c779d3055bff81ded683","tags":["Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com/security-alerts/cpuapr2022.html","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.qualys.com/2022/01/25/cve-2021-4034/pwnkit.txt","tags":["Exploit","Mitigation","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.secpod.com/blog/local-privilege-escalation-vulnerability-in-major-linux-distributions-cve-2021-4034/","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.starwindsoftware.com/security/sw-20220818-0001/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.suse.com/support/kb/doc/?id=000020564","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.vicarius.io/vsociety/posts/pwnkit-pkexec-lpe-cve-2021-4034","tags":["Exploit","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-4034","tags":["US Government Resource"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-4034","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}