Werk #19922: NGINX web servers (Linux) plugin crashed on hosts with kernel-owned sockets

Component

Checks & agents

Title

NGINX web servers (Linux) plugin crashed on hosts with kernel-owned sockets

Date

Sep 10, 2026

Level

Trivial Change

Class

Bug Fix

Compatibility

Compatible - no manual interaction needed

Checkmk versions & editions

3.0.0b1 Not yet released	Checkmk Community, Checkmk Pro, Checkmk Ultimate, Checkmk Cloud, Checkmk Ultimate MT
2.5.0p14 Not yet released	Checkmk Community, Checkmk Pro, Checkmk Ultimate, Checkmk Cloud, Checkmk Ultimate MT

The agent plugin nginx_status.py detects running NGINX servers from the output of ss -tlnp. Listening sockets that belong to no user space process, are listed without a process column. The plugin did not expect that and crashed with:

ValueError: not enough values to unpack (expected 6, got 5)

As a result, no NGINX services were reported on hosts that are affected by this bug. The plugin now skips such lines.

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