CVE-2026-29954: In KubePlus 4

In KubePlus 4.1.4, the mutating webhook and kubeconfiggenerator components have an SSRF vulnerability when processing the chartURL field of ResourceComposition resources. The field is only URL-encoded without validating the target address. More critically, when kubeconfiggenerator uses wget to download charts, the chartURL is directly concatenated into the command, allowing attackers to inject wget's `--header` option to achieve arbitrary HTTP header injection.