How severe is CVE-2021-20206?

CVE-2021-20206 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-20206 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20206?

CVE-2021-20206 affects Linuxfoundation Container Network Interface. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20206?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-20206 published?

CVE-2021-20206 was published on 2021-03-26 and last updated on 2026-06-17.

CVE-2021-20206

CVE-2021-20206 is a high-severity vulnerability in Linuxfoundation Container Network Interface with a CVSS 3.x base score of 7.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-22.

Key facts

Severity: High (CVSS 3.x base score 7.2)
CVSS v2: 6.5
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-22
Affected product: Linuxfoundation Container Network Interface
Published: 2021-03-26
Last modified: 2026-06-17

Description

An improper limitation of path name flaw was found in containernetworking/cni in versions before 0.8.1. When specifying the plugin to load in the 'type' field in the network configuration, it is possible to use special elements such as "../" separators to reference binaries elsewhere on the system. This flaw allows an attacker to execute other existing binaries other than the cni plugins/types, such as 'reboot'. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Frequently asked questions

What is CVE-2021-20206?: An improper limitation of path name flaw was found in containernetworking/cni in versions before 0.8.1. When specifying the plugin to load in the 'type' field in the network configuration, it is possible to use special elements such as "../" separators to reference binaries elsewhere on the system. This flaw allows an attacker to execute other existing binaries other than the cni plugins/types, such as 'reboot'. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.
How severe is CVE-2021-20206?: CVE-2021-20206 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-20206 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20206?: CVE-2021-20206 affects Linuxfoundation Container Network Interface. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20206?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-20206 published?: CVE-2021-20206 was published on 2021-03-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:linuxfoundation:container_network_interface:*:*:*:*:*:*:*:*

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