Printindex wihin KOMA script class without declare deprecated commands like \bf

Question

I'm using the document class scrartcl and want to have an index. This worked fine in the previous years using this source:

\documentclass{scrartcl}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[ngerman]{babel}
\usepackage{mathpazo}
\usepackage[scaled=0.95]{helvet}
\usepackage{courier}
\usepackage{makeidx}
\usepackage{showidx}


\makeindex

\begin{document}

\section{Text}
Here is a Term\index{Term}.

\printindex

\end{document}                                    

However, recently I got the error:

(./index.ind [1{/var/lib/texmf/fonts/map/pdftex/updmap/pdftex.map}]

! Class scrartcl Error: undefined old font command `\bf'.

See the scrartcl class documentation for explanation.
Type  H <return>  for immediate help.
 ...                                              

l.2 {\bf
         B}\nopagebreak%
? ^C! Interruption.
\GenericError  ...                                
                                                  \endgroup 
l.2 {\bf
         B}\nopagebreak%

I know that declare the missing command fix the error:

\DeclareOldFontCommand{\bf}{\normalfont\bfseries}{\mathbf}

Obviously I'm using some outdated way to generate an index, so my question is how to generate an index within KOMA script class without declare old deprecated commands?

Answer 1

Thank you Christian Hupfer and David Carlisle!

Indeed, the Makefile called makeindex with the -s parameter and referred to an style file which was unknown for me. Within the style file the \bf command was used. After replacing that, it works as expected. Thank you very much for your help!