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Werk #18922: Check HTTP web service: Fix text searches

Component Checks & agents
Title Check HTTP web service: Fix text searches
Date Dec 8, 2025
Level Trivial Change
Class Bug Fix
Compatibility Compatible - no manual interaction needed
Checkmk versions & editions
2.3.0p42 Checkmk Raw (CRE), Checkmk Enterprise (CEE), Checkmk Cloud (CCE), Checkmk MSP (CME)

In the Check HTTP web service ruleset, when configuring
Search for strings > search for header > Regular expression > Return CRITICAL [sic] if found, OK if not,
some bugs occured:

Wrong caption in ruleset
First of all: The caption should read Return WARN if found, OK if not, since WARN is the fixed state that will be returned for all failing header/body string/regex searches.
Please note that this will change starting with Checkmk 2.4.0p18, see Werk #18921.

Inverted header regex search didn't work
The service yielded an OK state most of the times, even if the regex was found in the headers.
This happened because the search iterates over all headers and stopped on first expected result. If the first header didn't contain the regex, the engine was satisfied and didn't continue.

Wrong info on inverted header regex searches
Also the appended (matched)/(not matched) info was swapped, leading to even more confusion.
Note: This info text will be enhanced a bit to be more meaningful, see also Werk #18921.

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