Babylon's malformed vote extensions are not rejected

published 2025-11-24 11mo ago modified 2026-03-03 8mo ago also GO-2025-4157

cvss: —; not scored
cisa kev: Not listed; not in CISA's catalog
epss: —; no score, EPSS covers CVEs only
public exploits: 0; none known

### Summary

Adversarial validators can send large vote extensions by using non-existing protobuf tags. This will result in the rejection of the subsequent block proposal. Eventually, all block proposals will be rejected by all validators.

### Impact

A small group of adversarial validators can cause a chain halt.

Patch / fix

fixed in 1 links 2

go github.com/babylonlabs-io/babylon/v4 4.1.0

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Affected packages

ecosystem	package	affected	fixed in
go	github.com/babylonlabs-io/babylon/v4	<4.1.0	4.1.0
go	github.com/babylonlabs-io/babylon	all versions	no fix listed
go	github.com/babylonlabs-io/babylon/v2	all versions	no fix listed
go	github.com/babylonlabs-io/babylon/v3	all versions	no fix listed

Classification

Weakness

CWE-770 Allocation of Resources Without Limits or Throttling

References

Sources

GitHub Advisory GHSA-2fcv-qww3-9v6h
OSV GO-2025-4157

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