Fabric vulnerable to crosslinking transaction attack

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.1 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

EPSS

• CVE-2023-46132: 0.52% estimated exploitation activity in the next 30 days; percentile 44.19 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Short summary 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…

Published by the source

14 Nov 2023, 20:28 UTC

Last modified by the source

14 Nov 2023, 21:37 UTC

Source last checked

26 Oct 2026, 15:00 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-v9w2-543f-h69m

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# Patch Next advisory brief: CVE-2023-46132

Advisory: Fabric vulnerable to crosslinking transaction attack
IDs: CVE-2023-46132, GHSA-v9w2-543f-h69m
Record: https://patchnext.com/advisories/cve-2023-46132 (revision 1, source checked 26 Oct 2026, 15:00 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/hyperledger/fabric 2.5.5, 2.2.14. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/hyperledger/fabric: affected >= 1.0.0-alpha, < 2.2.14; >= 2.3.0, < 2.5.5; fixed in 2.5.5, 2.2.14

## Suggested inspection (read-only)
- Go github.com/hyperledger/fabric: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/hyperledger/fabric.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-v9w2-543f-h69m (GitHub-reviewed advisory GHSA-v9w2-543f-h69m lists affected ranges: Go github.com/hyperledger/fabric >=1.0.0-alpha =2.3.0 <2.5.5)

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