CVE-2026-62337

MediumCVSS 6.9

Published: 30/10/2026(UTC)Updated: 02/11/2026(UTC)Translated: 30/10/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.30%

23th percentile - higher than 23% of all known CVEs

Summary

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.

Risk Assessment

May allow manipulation of aggregation computations and acceptance of invalid proofs depending on configuration, undermining verification integrity.

Recommendation

Update SNARK Verifier to version 0.2.5 or later.

Other vulnerabilities in SNARK Verifier

CVE-2026-61618Medium
SNARK Verifier is a generic (S)NARK verifier. Prior to 0.2.5, KZG accumulator public-instance limbs are decoded without consistently enforcing canonical limb bounds before elliptic-curve coordinate reconstruction. PlonkProof::read selects scalars using accumulator_indices and passes them to AccumulatorEncoding::from_repr. For the EVM loader, LimbsEncoding::from_repr forwards them to EvmLoader::ec_point_from_limbs in snark-verifier/src/loader/evm/loader.rs, where shl and add reconstruct coordinates before validate_ec_point checks the resulting affine point rather than the original limb bounds. The related native path in snark-verifier/src/pcs/kzg/accumulator.rs can reach assertion- or unwrap-based decoding and panic instead of returning a verification error. This allows noncanonical encodings at the verifier boundary and can crash the native verifier. Standard SDK aggregation circuits are expected to constrain accumulator limbs before this boundary, which limits practical exploitability. This issue is fixed in version 0.2.5.

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS