  The recent detection of gamma-ray burst GRB~221009A has attracted attention
due to its record brightness and first-ever detection of $\gtrsim 10$ TeV
$\gamma$ rays from a GRB. Despite being the second-nearest GRB ever detected,
at a redshift of $z=0.151$, the distance is large enough for severe attenuation
of $\gamma$-ray flux at these energies due to $\gamma\gamma\to e^\pm$ pair
production with the extragalactic background light (EBL). Here, we investigate
whether the presence of cosmic voids along the line of sight can significantly
impact the detectability of very-high energy (VHE, $>$ 100 GeV) gamma rays from
distant sources. Notably, we find that the gamma-gamma opacity for VHE gamma
rays can be reduced by approximately 10\% and up to 30\% at around 13 TeV, the
highest-energy photon detected from GRB~221009A, for intervening cosmic voids
along the line-of-sight with a combined radius of 110 Mpc, typically found from
voids catalogs, and 250 Mpc, respectively. This reduction is substantially
higher for TeV photons compared to GeV photons, attributable to the broader
target photon spectrum that TeV photons interact with. This finding implies
that VHE photons are more susceptible to variations in the EBL spectrum,
especially in regions dominated by cosmic voids. Our study sheds light on the
detection of $\gtrsim 10$ TeV gamma rays from GRB 221009A in particular, and on
the detection of extragalactic VHE sources in general.
