CVE-2021-4024Network attack vector

Unauthenticated VM service exposure via unrestricted gvproxy binding

Published Dec 23, 2021 · Updated Aug 3, 2024

Unrestricted network binding in Podman 3.3.0 through 3.4.2 allows remote attackers to expose private VM services through the host. The podman machine startHostNetworking function passes tcp://0.0.0.0:7777 to gvproxy, exposing its unauthenticated forwarding API on every host interface. Exploitation requires a running Podman machine and firewall access to port 7777; attackers can publish VM services or interrupt host services by redirecting ports.

CVSS severity6.5
Medium
EPSS probability1.06%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Unrestricted network binding in Podman 3.3.0 through 3.4.2 allows remote attackers to expose private VM services through the host. The podman machine startHostNetworking function passes tcp://0.0.0.0:7777 to gvproxy, exposing its unauthenticated forwarding API on every host interface. Exploitation requires a running Podman machine and firewall access to port 7777; attackers can publish VM services or interrupt host services by redirecting ports.

The record

CVE
CVE-2021-4024
Published
Dec 23, 2021
Updated
Aug 3, 2024
Vendor
Podman Container Tools
Product
Podman
Classifications
CWE-1327, T1090
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 23, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=podman 3.4.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Podman Container Tools · Podmanversion=podman 3.4.3

Published CVSS scores

6.4NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:P
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1327Binding to an Unrestricted IP Address
T1090Proxy

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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