Question 1

What is the EOL Risk Score for ClickHouse 25.5?

Accepted Answer

ClickHouse 25.5 has an EOL Risk Score™ of 40 out of 100, placing it in the Medium risk band. The score is calculated from four factors: EOL Recency (30/40), Attack Surface (10/30), CISA KEV Exposure (0/20), and Extended Support Availability (0/10).

Question 2

Is ClickHouse 25.5 still supported?

Accepted Answer

ClickHouse 25.5 is no longer supported — it has passed its end of life date (August 29, 2025). No further security patches will be issued. Upgrade to a supported version or obtain extended lifecycle support.

Question 3

When does ClickHouse 25.5 reach end of life?

Accepted Answer

ClickHouse 25.5 reached (or will reach) end of life on August 29, 2025. After this date, no security patches or bug fixes are issued by the vendor.

Question 4

What are the security risks of running ClickHouse 25.5 after end of life?

Accepted Answer

After end of life, ClickHouse 25.5 no longer receives security patches. Any newly discovered CVEs remain unpatched indefinitely. Organizations running EOL software also face compliance violations under SOC 2, PCI DSS, HIPAA, and ISO 27001, which require use of supported software versions.