CVE-2021-20206Network attack vector

Host binary execution via traversable plugin type

Published Mar 26, 2021 · Updated Aug 3, 2024

Path traversal in Container Network Interface CNI Plugins before 0.8.1 allows remote authenticated users to execute host binaries. The pkg/invoke FindInPath function accepts ../ and other path elements in the configuration type field, allowing lookup to escape CNI_PATH and select an existing executable. Reachability requires authority to add or remove network definitions, so successful exploitation runs the selected binary with the container runtime's host privileges.

CVSS severity7.2
High
EPSS probability1.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in Container Network Interface CNI Plugins before 0.8.1 allows remote authenticated users to execute host binaries. The pkg/invoke FindInPath function accepts ../ and other path elements in the configuration type field, allowing lookup to escape CNI_PATH and select an existing executable. Reachability requires authority to add or remove network definitions, so successful exploitation runs the selected binary with the container runtime's host privileges.

The record

CVE
CVE-2021-20206
Published
Mar 26, 2021
Updated
Aug 3, 2024
Vendor
Container Network Interface
Product
CNI Plugins
Classifications
CWE-20, CWE-22
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Mar 26, 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=containernetworking/cni 0.8.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Container Network Interface · CNI Pluginsversion=containernetworking/cni 0.8.1

Published CVSS scores

7.2GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

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.

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No observations available

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

Weakness, pattern, technique

CWE-20Improper Input Validation
CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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