Abstract

We investigate the equilibrium configurations of quark stars within Bumblebee gravity, a vector–tensor framework in which spontaneous Lorentz-symmetry breaking modifies the relativistic stellar structure equations. Employing a QCD-motivated equation-of-state based on the MIT bag model with perturbative corrections, we integrate the modified structure equations, and we obtain numerical interior solutions across a broad range of gravitational and microphysical parameters. The Lorentz-violating coupling induces only modest shifts in the maximum mass and radius, whereas the QCD interaction parameter has a markedly stronger impact on the stiffness of the equation of state and on the global stellar properties. The resulting mass–radius sequences remain compatible with current astrophysical constraints, including those from massive pulsars, gravitational-wave observations, and the compact object in HESS J1731 - 347. Stability is assessed through the turning-point criterion, the radial behaviour of the adiabatic index, and the causal propagation of sound, all of which indicate that the configurations are consistent with the standard necessary conditions for dynamical and microphysical viability. These findings show that Bumblebee gravity can accommodate observationally consistent quark-star solutions that remain consistent with standard necessary stability and causality conditions across an extended region of parameter space.