Calico Inserts Sensitive Information into Log File

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

7.2 · CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:N/VA:N/SC:H/SI:H/SA:H · score source

EPSS

• CVE-2026-6720: 0.22% estimated exploitation activity in the next 30 days; percentile 13.11 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

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.

Published by the source

28 May 2026, 18:30 UTC

Last modified by the source

2 Jul 2026, 18:08 UTC

Source last checked

26 Oct 2026, 15:24 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-3m4q-ggcj-j6m4

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# Patch Next advisory brief: CVE-2026-6720

Advisory: Calico Inserts Sensitive Information into Log File
IDs: CVE-2026-6720, GHSA-3m4q-ggcj-j6m4
Record: https://patchnext.com/advisories/cve-2026-6720 (revision 1, source checked 26 Oct 2026, 15:24 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.2)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/projectcalico/calicoctl/v3 3.31.6. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/projectcalico/calicoctl/v3: affected < 3.31.6; fixed in 3.31.6

## Suggested inspection (read-only)
- Go github.com/projectcalico/calicoctl/v3: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/projectcalico/calicoctl/v3.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-3m4q-ggcj-j6m4 (GitHub-reviewed advisory GHSA-3m4q-ggcj-j6m4 lists affected ranges: Go github.com/projectcalico/calicoctl/v3 >=0 <3.31.6)

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