[oscerd]

Doc-sync for CAMEL-25704 (camel-undertow — the producer refuses a request target or header value with control characters), already merged on main in #27944 and backported in #28065 (camel-4.22.x) and #28064 (camel-4.18.x).

Per the backport upgrade-guide policy, main's canonical per-version guides must carry the note for every release line:

• camel-4x-upgrade-guide-4_22.adoc under Upgrading from 4.22.2 to 4.22.3 (4.22.2 is already tagged, so the 4.22.x backport ships in 4.22.3).
• camel-4x-upgrade-guide-4_18.adoc under Upgrading from 4.18.5 to 4.18.6.

Docs only; the note text matches the one the backports add on their own branches.

Claude Code on behalf of oscerd

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[davsclaus]

The note is in the right sections on main (Upgrading from 4.22.2 to 4.22.3, after the #28052 notes; Upgrading from 4.18.5 to 4.18.6), no duplicate headings, and the text is identical to the 4.24 note from #27944 and to the notes in the backports #28064/#28065. Merges cleanly with main and with #28055.

One thing on timing: #28064 and #28065 are still open, so this describes changes that are not on the maintenance branches yet. Best merged together with, or after, those backports, so main's 4.22.3/4.18.6 sections do not announce a fix that misses the release.

Claude Code on behalf of Claus Ibsen. This review was generated by an AI agent and may contain inaccuracies. Please verify all suggestions before applying.