Bitcoin transaction fails with high threshold: “Signature must be null for CHECK(MULTI)SIG failed”
The world of Bitcoin transactions can be complex, especially when it comes to multisig wallets and the verification processes involved. Recently, a user reported that they failed to generate an event using the P2SH script on 3/4, but the same issue occurred with the P2SH script on 5/8. This result led them to investigate why the high threshold of the multisig wallet was causing such issues.
Problem: High threshold and failed event
In Bitcoin, multisig wallets require multiple signatures for a transaction to be valid. A common setup is to use a 3/4 or 5/8 multisig setup, where a total of four or five signatures are required. However, when using these setups at high thresholds, such as 32,000 or more, the validation process becomes increasingly complex.
In the case of the user reporting the issue, he successfully generated a transaction using the 3/4 P2SH script, but it failed because the multisig wallet limit was too high. The error message stated that the “Signature must be null to fail CHECK(MULTI)SIG” step failed.
Understanding the issue
The critical issue here is that when the number of transaction signatures exceeds a specified limit, the verification process fails. This is because Bitcoin’s CHECK(MULTI)SIG functionality relies on each individual script signing the transaction and verifying its validity before proceeding to finalize the transaction. When the number of signatures is too large, this step will fail.
A solution: reducing the limit
The user was able to resolve his issue by reducing the limit on his multisig wallet from 32,000 to a more manageable level. This adjustment allowed him to successfully generate transactions with a lower number of signatures.
Conclusion and Advice
When working with Bitcoin with multisig wallets, it is important to be aware of potential high limits that can cause issues during transaction creation. By understanding how these complex issues work and taking steps to mitigate them, users can avoid similar issues and ensure that their transactions are created successfully.
As always, it is important to note that this is a specific scenario and other users may face different challenges than other users when creating and validating Bitcoin transactions with multisig wallets. However, by understanding the basics of how high limits work in Bitcoin, you can take steps to avoid the issues reported in this case.
Tips to avoid similar issues:
- Monitor your transaction volume and adjust your multisig settings accordingly.
- Ensure your wallet settings are up to date and configured correctly.
- Keep your wallet software and plugins up to date, as any outdated versions can cause errors or conflicts with other wallets.
By learning about the potential pitfalls of high Bitcoin transaction limits and taking steps to mitigate them, you can enjoy a smoother experience working with multisig wallets for this popular cryptocurrency.