containerd CRI ExecSync Goroutine Leak Leading to Node-Level Denial of Service

Summary

containerd is an open-source container runtime. Prior to 1.7.35, 2.0.12, 2.2.8, and 2.3.5, containerd on Linux with the CRI plugin enabled can indefinitely block the drainExecSyncIO goroutine in internal/cri/server/container_execsync.go when CRI ExecSync is used by exec probes or lifecycle hooks that launch long-lived background child processes retaining standard input and output pipes. The input and output drain phase has no default timeout and did not stop when the request context was canceled, so repeated ExecSync invocations can accumulate blocked goroutines and host memory. The resulting resource exhaustion can cause the OOM killer to terminate containerd, leaving the container runtime unavailable until restart. Deployments not using containerd's CRI implementation and containers not running on Linux are not affected. This issue is fixed in versions 1.7.35, 2.0.12, 2.2.8, and 2.3.5.

Timeline

1. Sep 14, 2026, 5:18 PM UTCCVE published
2. Sep 14, 2026, 5:33 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. Sep 14, 2026, 5:34 PM UTCRecord last updated

Affected versions

• containerd containerd

  fixed in 1.7.35; From 2.0.0 · fixed in 2.0.12; From 2.2.0 · fixed in 2.2.8; From 2.3.0 · fixed in 2.3.5

• github.com/containerd/containerd/v2Go

  fixed in 2.0.12

• github.com/containerd/containerdGo

  fixed in 1.7.35

• github.com/containerd/containerd/v2Go

  From 2.2.0 · fixed in 2.2.8

• github.com/containerd/containerd/v2Go

  From 2.3.0 · fixed in 2.3.5

• github.com/containerd/containerd/v2Go

  fixed in 2.0.12; From 2.2.0 · fixed in 2.2.8; From 2.3.0 · fixed in 2.3.5

References 9