CVE intelligence and bounded remediation

CVE-2021-20291 — A deadlock vulnerability was found in 'github.com/containers/storage' in versions before 1.28.1

High CVSS 7.1

A deadlock vulnerability was found in 'github.com/containers/storage' in versions before 1.28.1. When a container image is processed, each layer is unpacked using `tar`. If one of those layers is not a valid `tar` archive this causes an error leading to an unexpected situation where the code indefinitely waits for the tar unpacked stream, which never finishes. An attacker could use this vulnerability to craft a malicious image, which when downloaded and stored by an application using containers/storage, would then cause a deadlock leading to a Denial of Service (DoS).

Severity
High
CVSS
7.1 (2.0)
Published
2021-04-01
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-667

Affected products

  • storage_project / storage
  • redhat / openshift_container_platform / 4.0
  • redhat / enterprise_linux / 8.0
  • fedoraproject / fedora / 33
  • fedoraproject / fedora / 34

Matched remediation archetype

Race condition, TOCTOU, and lifecycle synchronization

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Map concurrent actors, shared state, lock boundaries, signals, callbacks, retries, and check-then-use sequences in the affected path.
  • Determine whether untrusted users can influence timing, object names, filesystem state, or repeated state transitions.
  • Identify clustered and multi-process behavior that repository-local tests may not represent.

Remediate safely

  • Make the sensitive state transition atomic or protect it with a consistently ordered synchronization primitive.
  • Perform authorization and invariant checks on the same authoritative object and transaction used for the operation.
  • Use unique private resources, safe ownership transfer, and idempotent operations; add deterministic concurrency regression tests.

Authoritative sources

Complete CVE record and remediation plan

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