M1: Zero private key byte arrays in finally blocks#916
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Ensure private key bytes extracted via .ToBytes() are zeroed immediately after constructing the Key object, using CryptographicOperations.ZeroMemory in a finally block to guarantee cleanup even on exceptions. Files: - InvestorTransactionActions: zero investorPrivateKey bytes - SeederTransactionActions: zero privateKey bytes - SpendingTransactionBuilder: zero founderPrivateKey bytes This reduces the window during which raw key material exists in memory, mitigating memory-scraping attacks and crash dump exposure.
dangershony
approved these changes
Jul 4, 2026
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Summary
Zero private key byte arrays immediately after use via
CryptographicOperations.ZeroMemoryinfinallyblocks.Problem
When converting
AngorKeyto NBitcoinKeyvianew Key(privateKey.ToBytes()), the intermediate byte array containing raw private key material was never zeroed. It remained in managed memory until garbage collected, exposing it to memory-scraping attacks and crash dumps.Solution
Wrap the
new Key(bytes)call in a try/finally that zeros the byte array:csharp var keyBytes = privateKey.ToBytes(); Key key; try { key = new Key(keyBytes); } finally { CryptographicOperations.ZeroMemory(keyBytes); }Files Changed
BuildAndSignRecoverReleaseFundsTransactionSignInvestorRecoveryTransactionsTesting
All 154 shared tests pass.