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 Aug 27, 2026
  • CVSS 6.1 medium
  • 0.1% chance of exploitation in the next 30 days (EPSS)

Affected software

CVE-2026-19854 at the National Vulnerability Database