It was discovered that containerd incorrectly handled HTTP/2 SETTINGS frames. A remote attacker could possibly use this issue to cause containerd to enter an infinite loop, resulting in a denial of service. (CVE-2026-33814) Jakub Ciolek and Kyle Elliott discovered that containerd incorrectly handled group parsing when creating containers from images. An attacker could possibly use this issue to cause containerd to consume excessive memory, resulting in a denial of service. (CVE-2026-47262) Henry Beberman and Robert Prast discovered that containerd incorrectly validated image references when importing container checkpoints. An attacker could possibly use this issue to poison the local image cache and execute arbitrary code in other pods. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-50195) Robert Prast discovered that containerd incorrectly propagated labels from image configurations to containers. An attacker could possibly use this issue to execute arbitrary code on the host. (CVE-2026-53488) Yuming Zhang, Song Li, Sangwon Ryu, Henry Beberman, Robert Prast, Kyle Elliott and Zhenchen Wang discovered that containerd incorrectly validated symlinked paths when restoring container checkpoints. An attacker could possibly use this issue to read arbitrary files on the host, resulting in information disclosure. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-53489) Robert Prast discovered that containerd incorrectly trusted device interface annotations when restoring container checkpoints. An attacker could possibly use this issue to bypass resource allocation restrictions and inject devices or host mounts into a container. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-53492)
Impact
A bug was found in the containerd's CRI implementation where containerd doesn't put usernamespaced containers under the Kubernetes' cgroup hierarchy, therefore some Kubernetes limits are not honored. This may cause a denial of service of the Kubernetes node.
Patches
This bug has been fixed in containerd 2.0.5+ and 2.1.0+. Users should update to these versions to resolve the issue.
Workarounds
Disable usernamespaced pods in Kubernetes temporarily.
Credits
The containerd project would like to thank Rodrigo Campos Catelin and Piotr Rogowski for responsibly disclosing this issue in accordance with the containerd security policy.
For more information If you have any questions or comments about this advisory:
Open an issue in containerd Email us at security@containerd.io
To report a security issue in containerd: Report a new vulnerability Email us at security@containerd.io
End of life: 2/28/2023, End of support: 8/15/2022, Latest version: 1.5.18
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End of life: 3/4/2021, End of support: 3/4/2021, Latest version: 1.3.10
End of life: 10/15/2020, End of support: 3/26/2020, Latest version: 1.2.14
End of life: 10/15/2020, End of support: 3/26/2020, Latest version: 1.2.14
End of life: 10/23/2019, End of support: 10/23/2019, Latest version: 1.1.8
End of life: 10/23/2019, End of support: 10/23/2019, Latest version: 1.1.8
End of life: 12/5/2018, End of support: 12/5/2018, Latest version: 1.0.3
End of life: 12/5/2018, End of support: 12/5/2018, Latest version: 1.0.3