GHSA-m6wq-66p2-c8pc
Babylon Nil BlockHash in BLS vote extensions triggers panics in consensus handlers
Summary
A vulnerability exists in Babylon’s BLS vote extension processing where a malicious active validator can submit a VoteExtension with the block_hash field omitted from the protobuf serialization. Because protobuf fields are optional, unmarshalling succeeds but leaves BlockHash as nil. Babylon then dereferences this nil pointer in consensus-critical code paths (notably VerifyVoteExtension, and also proposal-time vote verification), causing a runtime panic.
Impact
Intermittent validator crashes at epoch boundaries, which would slow down the creation of the epoch boundary block.
Finder
Vulnerability discovered by:
- @GrumpyLaurie55348
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
What each source reports
GitHub Advisories Score used
Babylon Nil BlockHash in BLS vote extensions triggers panics in consensus handlers
Summary
A vulnerability exists in Babylon’s BLS vote extension processing where a malicious active validator can submit a VoteExtension with the block_hash field omitted from the protobuf serialization. Because protobuf fields are optional, unmarshalling succeeds but leaves BlockHash as nil. Babylon then dereferences this nil pointer in consensus-critical code paths (notably VerifyVoteExtension, and also proposal-time vote verification), causing a runtime panic.
Impact
Intermittent validator crashes at epoch boundaries, which would slow down the creation of the epoch boundary block.
Finder
Vulnerability discovered by:
- @GrumpyLaurie55348
- Record
GHSA-m6wq-66p2-c8pc- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-476
- Updated
- 2026-11-02
OSV
Babylon Nil BlockHash in BLS vote extensions triggers panics in consensus handlers
Summary
A vulnerability exists in Babylon’s BLS vote extension processing where a malicious active validator can submit a VoteExtension with the block_hash field omitted from the protobuf serialization. Because protobuf fields are optional, unmarshalling succeeds but leaves BlockHash as nil. Babylon then dereferences this nil pointer in consensus-critical code paths (notably VerifyVoteExtension, and also proposal-time vote verification), causing a runtime panic.
Impact
Intermittent validator crashes at epoch boundaries, which would slow down the creation of the epoch boundary block.
Finder
Vulnerability discovered by:
- @GrumpyLaurie55348
- Record
GHSA-m6wq-66p2-c8pc- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-476
- Updated
- 2026-11-02
OSVGO-2025-4211No score
Babylon Nil BlockHash in BLS vote extensions triggers panics in consensus handlers in github.com/babylonlabs-io/babylon
Babylon Nil BlockHash in BLS vote extensions triggers panics in consensus handlers in github.com/babylonlabs-io/babylon
- Record
GO-2025-4211- Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/babylonlabs-io/babylon/v4Go | before 4.2.0 | 4.2.0 |
github.com/babylonlabs-io/babylon/v3Go | through 3.0.0-snapshot.250805a | None known |
github.com/babylonlabs-io/babylon/v2Go | through 2.3.2 | None known |
github.com/babylonlabs-io/babylonGo | through 1.1.0 | None known |
github.com/babylonlabs-io/babylonGo | All versions | None known |
github.com/babylonlabs-io/babylon/v2Go | All versions | None known |
github.com/babylonlabs-io/babylon/v3Go | All versions | None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | GitHub Advisories, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
GHSA-m6wq-66p2-c8pc is a high vulnerability (CVSS 8.7) in github.com/babylonlabs-io/babylon/v4, published December 8, 2025. No source lists public exploit code. Fixed in github.com/babylonlabs-io/babylon/v4 4.2.0.