Vulnerability in Grafana Clickhouse Datasource

CVE-2026-19854

When the ClickHouse plugin uses Native protocol (the default) with PDC or secure SOCKS, it asks for TLS but the connection library ignores that and talks to ClickHouse in the clear. Username, password, queries, and results can be read on the hop after the proxy. The server certificate is never checked, and a configured client certificate is not sent.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.001 (0.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 0th percentile — 0.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

The 30-day trend appears once there are two daily scores.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-19854?
CVE-2026-19854 is a medium-severity vulnerability in Grafana Clickhouse Datasource, classified under Cleartext Transmission of Sensitive Information. CVSS score: 6.1/10. Published 2026-08-27.
How severe is CVE-2026-19854?
Medium severity. CVSS v3 base score is 6.1 out of 10.