  Hot exozodiacal dust (HEZD) found around main-sequence stars through
interferometric observations in the photometric bands H to L is located close
to the dust sublimation radius, potentially at orbital radii comparable to
those of close-in exoplanets. Consequently, HEZD has a potential influence on
the analysis of the scattered-light polarization of close-in exoplanets and
vice versa. We analyze the impact of HEZD on the polarimetric characterization
of close-in exoplanets. This study is motivated in particular by the recently
proven feasibility of exoplanet polarimetry. Applying the 3D Monte Carlo
radiative transfer code POLARIS in an extended and optimized version for
radiative transfer in exoplanetary atmospheres and an analytical tool for
modeling the HEZD, we simulated and compared the polarization characteristics
of the wavelength-dependent scattered-light polarization of HEZD and close-in
exoplanets. The varied parameters are the planetary phase angle
($0^\circ-180^\circ$), the dust grain radius ($0.02\ \mu$m $- \ 10\ \mu$m), the
HEZD mass ($10^{-10}$$\rm{M}_{\oplus}$ $-\ 10^{-8}$$\rm{M}_{\oplus}$), the
orbital inclination ($0^\circ-90^\circ$), the composition of the planetary
atmosphere (Mie and Rayleigh scattering atmosphere), the orbital radius of the
HEZD ($0.02$ au $-\ 0.4$ au), and the planetary orbital radius ($0.01$ au $-\
0.05$ au). The dust grain radius has the strongest influence on the
polarimetric analysis due to its significant impact on the wavelength-dependent
polarization characteristics and the total order of magnitude of the
scattered-light polarization. In certain scenarios, the scattered-light
polarization of the HEZD even exceeds that of the close-in exoplanet.
