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Actively exploited in the wild. This CVE is on the CISA Known Exploited Vulnerabilities list — treat remediation as urgent. Federal remediation due by 2 Jun 2023.
Debian LinuxOperating system · Debian

CVE-2021-3560

HIGH · 7.8 CVSS v3.1 Published 2022-02-16
Fix available
A fix is available. Upgrade to 0.119 or later.
See remediation →
96/100
Remediation priority · Urgent
In the wild Public exploit Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
It was found that polkit could be tricked into bypassing the credential checks for D-Bus requests, elevating the privileges of the requestor to the root user. This flaw could be used by an unprivileged local attacker to, for example, create a new local administrator. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A local privilege escalation vulnerability in polkit (policykit) allows an unprivileged attacker to bypass credential checks for D-Bus requests by sending specially crafted requests with a specific timing window, enabling the attacker to escalate to root privileges and create new local administrators.

MitigationApply the latest security patches for polkit immediately; this is a high-severity authentication bypass that requires urgent remediation regardless of other compensating controls.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Debian LinuxOperating system
Affected:= 11.0
Ubuntu LinuxOperating system
Affected:= 20.04
VirtualizationApplication
Affected:= 4.0
Virtualization HostApplication
Affected:= 4.0
Openshift Container PlatformApplication
Affected:= 4.7
PolkitApplication
Affected:< 0.119

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check polkit version with pkaction
    Run `pkaction --version` to retrieve the installed polkit version
    Affected if The version displayed is less than 0.119
  2. Check polkit package version on Debian/Ubuntu
    Run `dpkg -l polkit` or `dpkg -l policykit-1` and examine the Version field
    Affected if The version number is below 0.119
  3. Check polkit package version on RHEL/RHV/RVH
    Run `rpm -qa polkit` or `rpm -q polkit` and compare the output to the vulnerable version range
    Affected if The installed version is lower than 0.119-4.el8 or the equivalent vendor patch version
  4. Verify distribution and version matches affected list
    Run `cat /etc/os-release` or `lsb_release -a` to identify the OS and compare to Debian 11.0, Ubuntu 20.04, RHV 4.0, RHVH 4.0, or OCP 4.7
    Affected if The system runs one of these specific versions with a vulnerable polkit version
  5. Confirm polkit daemon is running
    Run `systemctl status polkit` or check for the polkitd process with `ps aux | grep polkit`
    Affected if Polkit is active and the version is below 0.119

A system is affected if it runs polkit version 0.119 or higher is not installed, regardless of distribution, or if it is a specifically listed affected distribution with an unpatched polkit version.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 0.119 or later
Fixed in 0.119
Vendor patch bugzilla.redhat.com →
Interim mitigation

Apply the latest security patches for polkit immediately; this is a high-severity authentication bypass that requires urgent remediation regardless of other compensating controls.

Recommended fix High confidence

polkit >= 0.119

  1. Update your system's package repository metadata: 'apt-get update' (Debian/Ubuntu) or 'dnf check-update' (RHEL/Fedora)
  2. Upgrade polkit to version 0.119 or later using your package manager: 'apt-get install polkit' (Debian/Ubuntu) or 'dnf update polkit' (RHEL/Fedora)
  3. Verify the installed version is 0.119 or higher: 'pktool --version' or 'pkexec --version'
  4. Restart any services that depend on polkit or reboot the system to ensure the fix takes effect
  5. For OpenShift Container Platform 4.7, apply the corresponding OCP security update as listed in the Red Hat security advisory
Caveat Minor: polkit update is low-risk but should be tested in non-production environments before deployment

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Debian Linux Exploited in the wild — priority engagement
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
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Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-3560 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data