The LSP (Language Server Protocol) plugin in KDE Kate before 21.12.2 and KTextEditor before 5.91.0 tries to execute the associated LSP server binary when opening a file of a given type. If this binary is absent from the PATH, it will try running the LSP server binary in the directory of the file that was just opened (due to a misunderstanding of the QProcess API, that was never intended). This can be an untrusted directory.
https://security.gentoo.org/glsa/202401-21