CVE-2026-6720: 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 stder

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 stder

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.

Description from the National Vulnerability Database, published by psirt@tigera.io

What it means for a small business

If your business uses Calico, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.22%, higher than 13% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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