CVE-2021-44225

Access-control bypass via destinationless D-Bus rules

Published Nov 26, 2021 · Updated Aug 4, 2024

Access-control bypass in Keepalived 2.2.4 and earlier allows attackers to inspect and modify service properties via D-Bus. The org.keepalived.Vrrp1.conf policy allowed Properties, Peer, and Introspectable interfaces without limiting send_destination, so those permissions applied to unrelated system-bus services. Exploitation requires system-bus access and another D-Bus service with a writable property; the resulting disclosure or modification is limited to properties exposed by that service.

CVSS severity5.4
Medium
EPSS probability1.08%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Access-control bypass in Keepalived 2.2.4 and earlier allows attackers to inspect and modify service properties via D-Bus. The org.keepalived.Vrrp1.conf policy allowed Properties, Peer, and Introspectable interfaces without limiting send_destination, so those permissions applied to unrelated system-bus services. Exploitation requires system-bus access and another D-Bus service with a writable property; the resulting disclosure or modification is limited to properties exposed by that service.

The record

CVE
CVE-2021-44225
Published
Nov 26, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Nov 26, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.4UbuntuCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
8.1Amazon LinuxCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
5.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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