Vulnerability-Lookup

GHSA-QGR2-XGQV-24X8

Vulnerability from github – Published: 2022-01-29 00:00 – Updated: 2025-10-22 00:32

Details

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

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Show details on source website

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{
  "affected": [],
  "aliases": [
    "CVE-2021-4034"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-125",
      "CWE-787"
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    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-01-28T20:15:00Z",
    "severity": "HIGH"
  },
  "details": "A local privilege escalation vulnerability was found on polkit\u0027s 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\u0027t 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\u0027ll 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.",
  "id": "GHSA-qgr2-xgqv-24x8",
  "modified": "2025-10-22T00:32:28Z",
  "published": "2022-01-29T00:00:42Z",
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      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-4034"
    },
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    {
      "type": "WEB",
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      "type": "WEB",
      "url": "https://www.qualys.com/2022/01/25/cve-2021-4034/pwnkit.txt"
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      "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-330556.pdf"
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    {
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      "url": "http://packetstormsecurity.com/files/166196/Polkit-pkexec-Local-Privilege-Escalation.html"
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      "url": "http://packetstormsecurity.com/files/166200/Polkit-pkexec-Privilege-Escalation.html"
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  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
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}

CVE-2021-4034 (GCVE-0-2021-4034)

Vulnerability from cvelistv5 – Published: 2022-01-28 00:00 – Updated: 2026-08-15 03:55

Summary

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: active Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2022-06-27 00:00 UTC

CWE

CWE-787 - (CWE-787|CWE-125)

Assigner

redhat redhat root

References

13 references

URL	Tags
https://access.redhat.com/security/vulnerabilitie…
https://www.qualys.com/2022/01/25/cve-2021-4034/p…
https://bugzilla.redhat.com/show_bug.cgi?id=2025869
https://gitlab.freedesktop.org/polkit/polkit/-/co…
https://www.oracle.com/security-alerts/cpuapr2022.html
http://packetstormsecurity.com/files/166196/Polki…
http://packetstormsecurity.com/files/166200/Polki…
https://www.suse.com/support/kb/doc/?id=000020564
https://cert-portal.siemens.com/productcert/pdf/s…
https://www.starwindsoftware.com/security/sw-2022…
https://www.secpod.com/blog/local-privilege-escal…
https://www.vicarius.io/vsociety/posts/pwnkit-pke…
https://www.cisa.gov/known-exploited-vulnerabilit…	government-resource

Impacted products

1 product

Vendor	Product	Version
n/a	polkit	Affected: all

Show details on NVD website

JSON

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.