CVE-2026-95837: containerd CRI plugin: Checkpoint restore bypasses destination security context
Impact
A vulnerability in containerd's CRI implementation allows a container restored from an untrusted checkpoint via the CreateContainer API to bypass the destination security context and execute with elevated privileges. When restoring a container from a checkpoint archive or annotated OCI image, CRIU restores process credentials, Linux capabilities, nonewprivs, and seccomp state directly from checkpoint data rather than enforcing the destination CRI ContainerConfig. An attacker who can run a container with a crafted checkpoint image can execute processes as root with full capabilities and no enforced seccomp filters despite restrictive security policies requested by the orchestrator. Additionally, containerd's CRI status reporting reflects the requested configuration rather than the actual restored process state, masking the privilege discrepancy from orchestrators. This issue affects Linux systems running containerd with CRI checkpoint restore enabled; users not utilizing CRI checkpoint restore are not affected.
Patches
This bug has been addressed in containerd 2.2.7 and 2.3.4 by disabling checkpoint restore via CreateContainer by default. The feature has been removed entirely in containerd 2.4.0. Users should update to these versions to resolve the issue. Running containers that were restored from untrusted checkpoints should be stopped, deleted, and recreated.
Users who rely on restore via the CreateContainer API can re-enable the feature by setting the new enableexperimentalrestoreviacreate configuration option. However, enabling restore via CreateContainer leaves this vulnerability present, as containerd cannot enforce destination security policy during CRIU process restoration.
Workarounds
On unpatched versions, containerd does not provide a configuration option to disable checkpoint restore via CreateContainer. Deployments should restrict container creation permissions to trusted users, validate container image registries, or use admission controllers to reject images containing checkpoint data.
References
CRIU image security
Credits
The containerd project would like to thank @l2yyd5 and @berkpolatCE 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
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Other sources
containerd is an open-source container runtime. From 2.1.0 until 2.2.7 and 2.3.4, containerd's CRI CreateContainer checkpoint restore is vulnerable because CRIU restores process security state from checkpoint data instead of enforcing the destination ContainerConfig. An attacker who can create a container from a crafted checkpoint can supply restored credentials, capabilities, nonewprivs, and seccomp state. The restored process can run as root with full capabilities and no enforced seccomp filters while CRI status reports the requested configuration. Systems that do not use CRI checkpoint restore are not affected. This issue is fixed in versions 2.2.7 and 2.3.4.
— NVD
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
go/github.com/containerd/containerd/v2to a version that resolves this vulnerability.Fixed in 2.3.4 - Upgrade
Upgrade
go/github.com/containerd/containerd/v2to a version that resolves this vulnerability.Fixed in 2.2.7 - Upgrade
Upgrade
containerdto a version that resolves this vulnerability.Fixed in 2.2.7 - Upgrade
Upgrade
containerdto a version that resolves this vulnerability.Fixed in 2.3.4 - Compensating control
Restrict container creation permissions to trusted users, validate container image registries, or use admission controllers to reject images containing checkpoint data.
- Operational
Stop, delete, and recreate running containers that were restored from untrusted checkpoints.
Event History
Frequently Asked Questions
Which deployments are exposed to this issue?
Only systems that use the containerd CRI plugin's CreateContainer checkpoint restore functionality are affected. Systems that do not use CRI checkpoint restore are not affected.
What access does an attacker need to exploit it?
The attacker needs the ability to create a container from a crafted checkpoint. The provided severity vector indicates this is locally exploitable and requires low privileges, with no user interaction.
What can a crafted checkpoint cause after restoration?
It can restore attacker-controlled credentials, capabilities, no_new_privs, and seccomp state instead of applying the destination ContainerConfig. This can result in a process running as root with full capabilities and without enforced seccomp filters, while CRI status reports the requested configuration.
How can I determine whether a restored container is affected?
Compare the process's actual credentials, capabilities, no_new_privs setting, and seccomp state with the destination ContainerConfig. Affected restores may have privileged runtime state even though CRI status reports the requested configuration.
What versions contain the fix?
The issue is fixed in containerd versions 2.2.7 and 2.3.4. Versions from 2.1.0 up to those fixed releases are affected when CRI checkpoint restore is used.