An easy and convenient method to achieve this is the use of the Luche reduction.[1,2]
The ‘organic chemist’s bible’, Strategic Applications of Named Reactions in Organic Synthesis by L. Kürti and B. Czakó notes on the page of the Luche reduction (p. 268):
8) the combination of $\ce{CeCl3/NaBH4}$ is excellent for the chemoselective reduction of ketones in the presence of aldehydes, since under these conditions aldehydes undergo rapid acetalization, which prevents their reduction.
Indeed, when a $1:1$ mixture of hexanal and cyclohexanone is subjected to Luche conditions with $1.5~\mathrm{eq}$ of $\ce{NaBH4}$, a quantitative yield of cyclohexanol and a nigh-quantitative ($98~\%$) of hexanal are recovered. Without the addition of $\ce{CeCl3}$, $1.5~\mathrm{eq}$ reduce cyclohexanone quantitatively and $49~\%$ of hexan-1-ol are also recovered.[1]
Reference and note:
[1]: J. L. Luche, A. L. Gemal, J. Am. Chem. Soc. 1979, 101, 5848. DOI: 10.1021/ja00513a075.
[2]: The article [1] is only two pages short. The first page is displayed as an ‘abstract’ on pubs.acs.org (‘in lieu of an abstract’, ibid.). Thus, opening the abstract of S. Nagase, T. Fueno, K. Morokama, J. Am. Chem. Soc. 1979, 101, 5849 (DOI: 10.1021/ja00513a076) can serve as a cheap hack to see the entire article.