SNARK Verifier: Halo 2 aggregation mishandles point-at-infinity proof elements

SNARK Verifier is a generic (S)NARK verifier. Prior to 0.2.5, the Halo 2 aggregation circuit can mishandle proof points encoded as the point at infinity. EcPointLoader::multi_scalar_multiplication places a Value::Assigned(_) base paired with Value::Constant(ONE) into its unscaled variable-base list and passes it directly to sum_with_const. The default shim delegates to halo2-lib EccChip::sum, whose incomplete affine addition assumes nonidentity input points. A prover-controlled proof point encoded as (0, 0) can therefore enter the final aggregation sum through the scalar-one shortcut and affect the MSM or accumulator computation. Practical exploitability depends on the surrounding aggregation and final-decider checks; the advisory does not establish universal acceptance of invalid proofs. This issue is fixed in version 0.2.5.