  Chirally enhanced supersymmetric QCD corrections to FCNC processes are
investigated in the framework of the MSSM with generic sources of flavor
violation. These corrections arise from flavor-changing self-energy diagrams
and can be absorbed into a finite renormalization of the squark-quark-gluino
vertex. In this way enhanced two-loop and even three-loop diagrams can be
efficiently included into a leading-order (LO) calculation. Our corrections
substantially change the values of the parameters delta^{d,LL}_{23},
delta^{d,LR}_{23}, delta^{d,RL}_{23}, and delta^{d,RR}_{23} extracted from
Br[B->X_s gamma] if tan(beta) is large. We find stronger (weaker) constraints
compared to the LO result for negative (positive) values of mu. The constraints
on delta^{d,LR,RL}_{13} and delta^{d,LR,RL}_{23} from B_d mixing and B_s mixing
change drastically if the third-generation squark masses differ from those of
the first two generations. K mixing is more strongly affected by the chirally
enhanced loop diagrams and even sub-percent deviations from degenerate down and
strange squark masses lead to profoundly stronger constraints on
delta^{d,LR,RL}_{12}.
