CVE-2026-6720: Calicoctl leaks cluster credentials to stderr when verbose logging is enabled

Severity: high (CVSS 7.2 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-28 · updated 2026-06-17
Weakness: CWE-532

Description

When calicoctl is invoked with --log-level=info or --log-level=debug, the client prints the full contents of its loaded connection-configuration struct to stderr in a single log line. The struct embeds every credential calicoctl uses to talk to the cluster — inline kubeconfig (with bearer token), Kubernetes API bearer token, etcd password, and inline PEM-encoded etcd client certificate and key. Any reader of that stderr stream — CI job logs, session-recording archives, shared support-ticket transcripts, or local filesystem viewers on the host that ran calicoctl — can extract these credentials with zero Kubernetes privilege. calicoctl's default log level is panic, so this issue only triggers when verbose logging is explicitly enabled.

Affected products

Tigera Calico: before 3.32.0 — fixed in 3.32.0
Tigera Calico Cloud: before 22.4.0 — fixed in 22.4.0
Tigera Calico Enterprise: before 3.21.7 — fixed in 3.21.7

How to fix

Upgrade to a fixed version: Tigera Calico 3.32.0; Tigera Calico Cloud 22.4.0; Tigera Calico Enterprise 3.21.7. Check the vendor advisory for mitigations.

References

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