CVE-2026-32129

CVE-2026-32129 is a high-severity cryptographic vulnerability affecting the Poseidon V1 (PoseidonSponge) hash function within the soroban-poseidon library. This flaw allows for trivial hash collisions when variable-length inputs are provided, specifically when the input length is less than the sponge rate, due to implicit zero-filling. With a CVSS score of 8.7 (HIGH), this vulnerability has a network attack vector and low attack complexity, leading to a high impact on data integrity as attackers can forge identical hashes for different inputs. There is currently no evidence of active exploitation, nor are there any public exploits available in common databases like Metasploit or ExploitDB, and community discussion remains minimal.