CVE-2026-32129

soroban-poseidon provides Poseidon and Poseidon2 cryptographic hash functions for Soroban smart contracts. Poseidon V1 (PoseidonSponge) accepts variable-length inputs without injective padding. When a caller provides fewer inputs than the sponge rate (inputs.len() < T - 1), unused rate positions are implicitly zero-filled. This allows trivial hash collisions: for any input vector [m1, ..., mk] hashed with a sponge of rate > k, hash([m1, ..., mk]) equals hash([m1, ..., mk, 0]) because both produce identical pre-permutation states. This affects any use of PoseidonSponge or poseidon_hash where the number of inputs is less than T - 1 (e.g., hashing 1 input with T=3). Poseidon2 (Poseidon2Sponge) is not affected.

CVSS

No CVSS.

References

Link	Resource
https://github.com/stellar/rs-soroban-poseidon/pull/10
https://github.com/stellar/rs-soroban-poseidon/releases/tag/v25.0.1
https://github.com/stellar/rs-soroban-poseidon/security/advisories/GHSA-g2p6-hh5v-7hfm

Configurations

No configuration.

History

No history.

Information

Published : 2026-03-12 18:16

Updated : 2026-03-12 21:07

NVD link : CVE-2026-32129

Mitre link : CVE-2026-32129

CVE.ORG link : CVE-2026-32129

JSON object : View

Products Affected

No product.

CWE

CWE-328

Use of Weak Hash

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