{"id":"BIT-hyperledger-fabric-tools-2023-46132","summary":"Crosslinking transaction attack in hyperledger/fabric","details":"Hyperledger Fabric is an open source permissioned distributed ledger framework. Combining two molecules to one another, called \"cross-linking\" results in a molecule with a chemical formula that is composed of all atoms of the original two molecules. In Fabric, one can take a block of transactions and cross-link the transactions in a way that alters the way the peers parse the transactions. If a first peer receives a block B and a second peer receives a block identical to B but with the transactions being cross-linked, the second peer will parse transactions in a different way and thus its world state will deviate from the first peer. Orderers or peers cannot detect that a block has its transactions cross-linked, because there is a vulnerability in the way Fabric hashes the transactions of blocks. It simply and naively concatenates them, which is insecure and lets an adversary craft a \"cross-linked block\" (block with cross-linked transactions) which alters the way peers process transactions. For example, it is possible to select a transaction and manipulate a peer to completely avoid processing it, without changing the computed hash of the block. Additional validations have been added in v2.2.14 and v2.5.5 to detect potential cross-linking issues before processing blocks. Users are advised to upgrade. There are no known workarounds for this vulnerability.","aliases":["BIT-hyperledger-fabric-orderer-2023-46132","BIT-hyperledger-fabric-peer-2023-46132","CVE-2023-46132","GHSA-v9w2-543f-h69m"],"modified":"2026-09-10T16:01:10.576755731Z","published":"2024-07-18T19:21:27.761Z","database_specific":{"cpes":["cpe:2.3:a:hyperledger:fabric:*:*:*:*:*:*:*:*"],"severity":"High"},"references":[{"type":"ADVISORY","url":"https://github.com/hyperledger/fabric/security/advisories/GHSA-v9w2-543f-h69m"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-46132"}],"affected":[{"package":{"name":"hyperledger-fabric-tools","ecosystem":"Bitnami","purl":"pkg:bitnami/hyperledger-fabric-tools"},"ranges":[{"type":"SEMVER","events":[{"introduced":"1.0.0"},{"fixed":"2.2.14"},{"introduced":"2.3.0"},{"fixed":"2.5.5"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/hyperledger-fabric-tools/BIT-hyperledger-fabric-tools-2023-46132.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L"}]}],"schema_version":"1.9.0"}