Polygon software bug caused some RPC and Bor nodes to fall out of sync, but block production continued. The Polygon Foundation executed a hard fork and released Heimdall v0.3.1 and Bor 2.2.11 beta2 to purge the faulty milestone and restore consensus and finality.
-
RPC nodes and Bor forks were temporarily divergent
-
Consensus and finality were restored after a coordinated hard fork and database purge
-
Node operators should update Heimdall and Bor and resync affected RPCs
Polygon software bug disrupted RPC nodes but not block production — check fixes, steps for node operators, and latest status from Polygon Foundation. Read now.
The bug impacted some remote procedure call (RPC) nodes, causing them to fall out of sync, but did not impact onchain block production.
What caused the Polygon software bug?
The Polygon software bug originated from a faulty proposal by a validator that pushed certain Bor nodes onto divergent forks. This discrepancy affected RPC relays and node synchronization, while Bor continued producing blocks and onchain block production remained uninterrupted.
How did Polygon restore consensus and finality?
Polygon Foundation executed a coordinated hard fork, deploying Heimdall v0.3.1 and Bor 2.2.11 beta2 to remove the problematic milestone from node databases. Polygon co-founder Sandeep Nailwal confirmed the rollout and stated that checkpoints and milestones are now finalizing normally.
Source: Polygon Foundation
The issue primarily affected RPC nodes, which relay blockchain state to wallets and dApps. Because Bor continued producing blocks, onchain transaction ordering and block production were not halted, preventing broader network stoppage.
Polygon’s response focused on purging the malformed milestone from Heimdall and Bor databases. Heimdall v0.3.1 includes the hard fork that deletes the identified milestone, while Bor 2.2.11 beta2 purges the same record to bring nodes back into consensus.
When did Polygon encounter a similar outage before?
Polygon experienced a comparable incident in July when Heimdall mainnet halted for about an hour after a validator exited the network. Like the recent bug, block production on Bor never stopped; affected RPCs needed to resynchronize to reflect the live chain state.
Transactions on Polyscan, the block explorer for Polygon, are displaying properly. Source: Polygon Scan
How should node operators respond now?
Node operators should update to Heimdall v0.3.1 and Bor 2.2.11 (beta2), verify database purges completed successfully, and resynchronize any RPC instances that show stale state. Monitor official Polygon Foundation updates and block explorers such as Polygon Scan for confirmation of finality.
| Date | Affected component | Impact on block production | Resolution |
|---|---|---|---|
| July 2025 | Heimdall mainnet (consensus relay) | Block production continued on Bor; consensus relay paused ~1 hour | Validator exit handled; RPCs resynced |
| September 2025 | Faulty validator proposal → Bor forks & RPC divergence | Block production continued; some RPC nodes out of sync | Hard fork + Heimdall v0.3.1 & Bor 2.2.11 beta2; purged milestone |
Frequently Asked Questions
Did the Polygon software bug affect transactions?
Onchain transactions continued to be produced and recorded because Bor block production did not stop. Some RPC endpoints displayed stale state until node resynchronization completed, but finalized blocks remained available on block explorers.
How can I check if my RPC node is in sync?
Compare your node’s latest block hash and height to a trusted block explorer (e.g., Polygon Scan) and monitor Heimdall checkpoint finality. If block heights or hashes diverge, upgrade Heimdall and Bor, then resync the database following official guidance.
Key Takeaways
- Immediate effect: RPC nodes and some Bor nodes fell out of sync, but block production continued.
- Fix applied: Heimdall v0.3.1 and Bor 2.2.11 beta2 purged the faulty milestone and restored finality.
- Action for operators: Update binaries, verify database purges, resync RPCs, and monitor official Polygon Foundation communications.
Conclusion
Polygon’s latest software bug highlights the operational challenges of modern layer-2 networks as they scale feature sets and cross-chain integrations. The Polygon Foundation’s prompt hard fork and targeted node upgrades restored consensus and finality. Node operators should update Heimdall and Bor and resynchronize RPCs to ensure continued network reliability.
Published: 2025-09-10 | Updated: 2025-09-10
