Cyber Resilience

CVE-2021-21334

Medium

Published: 10 March 2021

Published
10 March 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 6.3 CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
EPSS Score 0.0040 61.5th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-21334 is a medium-severity Exposure of Resource to Wrong Sphere (CWE-668) vulnerability in Linuxfoundation Containerd. Its CVSS base score is 6.3 (Medium).

Operationally, ranked in the top 38.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

In containerd (an industry-standard container runtime) before versions 1.3.10 and 1.4.4, containers launched through containerd's CRI implementation (through Kubernetes, crictl, or any other pod/container client that uses the containerd CRI service) that share the same image may receive incorrect environment…

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variables, including values that are defined for other containers. If the affected containers have different security contexts, this may allow sensitive information to be unintentionally shared. If you are not using containerd's CRI implementation (through one of the mechanisms described above), you are not vulnerable to this issue. If you are not launching multiple containers or Kubernetes pods from the same image which have different environment variables, you are not vulnerable to this issue. If you are not launching multiple containers or Kubernetes pods from the same image in rapid succession, you have reduced likelihood of being vulnerable to this issue This vulnerability has been fixed in containerd 1.3.10 and containerd 1.4.4. Users should update to these versions.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

linuxfoundation
containerd
≤ 1.3.10 · 1.4.0 — 1.4.4
fedoraproject
fedora
33, 34

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-668

Controls whether organization resources are exposed to external system spheres by permitting or prohibiting their use.

addresses: CWE-668

The control ensures information is not released into a security sphere where the recipient lacks matching access authorizations.

addresses: CWE-668

The control ensures information resources are not exposed to the incorrect (public) sphere through review and authorization.

addresses: CWE-668

Protects against data mining that would expose resources to unauthorized spheres by enforcing detection and controls.

addresses: CWE-668

Restricts information flows to ensure resources are not exposed to incorrect or unauthorized spheres.

addresses: CWE-668

Controlling internal connections prevents exposure of resources to unintended internal spheres.

addresses: CWE-668

Knowing exact processing and storage locations helps avoid exposure of resources to incorrect spheres.

addresses: CWE-668

The control prevents exposure of the media resource to the wrong security sphere.

References