GHSA-36xw-fx78-c5r4 CVE-2020-15257 GO-2022-0784

containerd-shim API Exposed to Host Network Containers

Medium Go

Severity: 5.2 / 10; Medium · CVSS 3.1
Exploit chance (EPSS): 3.12%; Chance of exploitation in the next 30 days. Higher than 87.86% of scored vulnerabilities.
Known exploited: No; Not in CISA's catalog
Weakness: CWE-669 Incorrect Resource Transfer Between Spheres
Fix: 1.3.9; Upgrade github.com/containerd/containerd to this version or later

Description

Impact

Access controls for the shim’s API socket verified that the connecting process had an effective UID of 0, but did not otherwise restrict access to the abstract Unix domain socket. This would allow malicious containers running in the same network namespace as the shim, with an effective UID of 0 but otherwise reduced privileges, to cause new processes to be run with elevated privileges.

Specific Go Packages Affected

github.com/containerd/containerd/cmd

Patches

This vulnerability has been fixed in containerd 1.3.9 and 1.4.3. Users should update to these versions as soon as they are released. It should be noted that containers started with an old version of containerd-shim should be stopped and restarted, as running containers will continue to be vulnerable even after an upgrade.

Workarounds

If you are not providing the ability for untrusted users to start containers in the same network namespace as the shim (typically the "host" network namespace, for example with docker run --net=host or hostNetwork: true in a Kubernetes pod) and run with an effective UID of 0, you are not vulnerable to this issue.

If you are running containers with a vulnerable configuration, you can deny access to all abstract sockets with AppArmor by adding a line similar to deny unix addr=@**, to your policy.

It is best practice to run containers with a reduced set of privileges, with a non-zero UID, and with isolated namespaces. The containerd maintainers strongly advise against sharing namespaces with the host. Reducing the set of isolation mechanisms used for a container necessarily increases that container's privilege, regardless of what container runtime is used for running that container.

Credits

The containerd maintainers would like to thank Jeff Dileo of NCC Group for responsibly disclosing this issue in accordance with the containerd security policy and for reviewing the patch.

For more information

If you have any questions or comments about this advisory:

Open an issue
Email us at security@containerd.io if you think you’ve found a security bug.

Affected versions

Go

Package	Vulnerable	Fixed in
github.com/containerd/containerd	`< 1.3.9`	`1.3.9`
github.com/containerd/containerd	`>= 1.4.0, < 1.4.3`	`1.4.3`
github.com/containerd/containerd	`< 1.3.9` `>= 1.4.0, < 1.4.3`	`1.3.9` `1.4.3`

How to fix

Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.

github.com/containerd/containerd Go → `1.3.9`

go

go get github.com/containerd/containerd@v1.3.9 && go mod tidy

Severity breakdown

CVSS 3.1 5.2

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Changed
Confidentiality: Low
Integrity: Low
Availability: None

Weakness

CWE-669: Incorrect Resource Transfer Between Spheres

The product does not properly transfer a resource/behavior to another sphere, or improperly imports a resource/behavior from another sphere, in a manner that provides unintended control over that resource.

References

Advisories

nvd.nist.gov/vuln/detail/CVE-2020-15257

Timeline

May 24, 2021 Published
Sep 10, 2026 Last updated by the source
Oct 31, 2026 Latest EPSS score

Advisory	Severity	Why it's related
GHSA-rp3h-jf77-q9p4 containerd: Unpack DoS via repeated opaque whiteouts	Medium	Also affects github.com/containerd/containerd
GO-2026-6791 containerd CRI plugin: Checkpoint restore bypasses destination security context	High	Also affects github.com/containerd/containerd
GHSA-pg57-6jwg-q645 Containerd has image-pull DoS via crafted OCI index graph amplification	Medium	Also affects github.com/containerd/containerd
GHSA-7jxh-36q5-gcqv containerd: CRI ExecSync Goroutine Leak Leads to Node-Level Denial of Service	Medium	Also affects github.com/containerd/containerd
GO-2026-5064 containerd CRI checkpoint restore CDI annotation smuggling	Critical	Also affects github.com/containerd/containerd
GO-2026-5622 Arbitrary host CRI log file read via symlink following in CRI checkpoint restore	Medium	Also affects github.com/containerd/containerd
GHSA-xhf5-7wjv-pqxp containerd CRI — image-config `LABEL` flows to restart-monitor `binary://` logger: host-root command execution from an image pull	High	Also affects github.com/containerd/containerd
GO-2026-5338 containerd: CRI checkpoint import allows local image tag poisoning	Critical	Also affects github.com/containerd/containerd

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