Exploitation evidence
Known exploited · CISA KEV listed
Added 2022-06-27. Ransomware campaign use: Known.
CISA required action: Apply updates per vendor instructions.
CISA due date: 2022-07-18. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
n/a / polkit
Default status: Not specified
- affected: all
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
CVE Program record ↗ · Download tracked evidence as JSON
- 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
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-4034
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.94921,
"percentile": 0.99862
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.94921,
"percentile": 0.99861
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.94921,
"percentile": 0.99861
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.94921,
"percentile": 0.99861
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.94921,
"percentile": 0.99861
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.94921,
"percentile": 0.99861
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.94921,
"percentile": 0.9986
}05 Nov 2026, 06:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
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}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
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"epss": 0.94921,
"percentile": 0.9986
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.94921,
"percentile": 0.9986
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.94921,
"percentile": 0.9986
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
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"cwes": [
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"dateAdded": "2022-06-27",
"dueDate": "2022-07-18",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Known",
"notes": "https://nvd.nist.gov/vuln/detail/CVE-2021-4034",
"product": "Polkit",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "The Red Hat polkit pkexec utility contains an out-of-bounds read and write vulnerability that allows for privilege escalation with administrative rights.",
"vendorProject": "Red Hat",
"vulnerabilityName": "Red Hat Polkit Out-of-Bounds Read and Write Vulnerability"
}