Skip to content

Latest commit

 

History

History
38 lines (31 loc) · 5.16 KB

threat-modeling.md

File metadata and controls

38 lines (31 loc) · 5.16 KB

Threat Model Analysis for mimblewimble/grin

Threat: Double-Spending (via Node Compromise or 51% Attack)

  • Description: An attacker gains control of a Grin node (or a significant portion of the network's mining power, constituting a 51% attack) and attempts to double-spend coins. The compromised node could present conflicting transaction histories to different parts of the network or to applications. This involves manipulating the blockchain itself.
    • Impact: Loss of funds for users and applications relying on the network. Erosion of trust in the Grin cryptocurrency.
    • Affected Grin Component: The entire Grin node software, particularly the consensus mechanism (grin_core::consensus), block validation (grin_core::core::block), and transaction pool (grin_core::core::transaction). This is a fundamental attack on the blockchain's integrity.
    • Risk Severity: Critical
    • Mitigation Strategies:
      • Sufficient Confirmations: Applications should wait for a sufficient number of blocks to be mined on top of a transaction before considering it final. The number of confirmations should be proportional to the value of the transaction and the acceptable risk. This mitigates the impact of a successful double-spend, but doesn't prevent it on the network.
      • Multiple Node Verification: Query multiple, independent Grin nodes and compare their responses. Discrepancies could indicate a double-spend attempt or a compromised node. Again, this is a detection/mitigation strategy at the application level, not a prevention within Grin itself.
      • (Grin Network Level - Not directly controllable by application developers): A sufficiently decentralized and robust mining network is the primary defense against 51% attacks.

Threat: Grin Node Software Vulnerability (Elevation of Privilege / Remote Code Execution)

  • Description: A vulnerability in the Grin node software itself (e.g., a buffer overflow, format string vulnerability, or other code execution flaw) allows an attacker to gain control of the server running the node. This is distinct from vulnerabilities in applications using Grin.
    • Impact: Complete compromise of the Grin node, potentially leading to double-spending, censorship of transactions, data theft (though limited by Mimblewimble's privacy), or the use of the compromised server for other malicious purposes.
    • Affected Grin Component: Potentially any part of the Grin node software, depending on the specific vulnerability. This could include the P2P networking layer (grin_p2p), the consensus mechanism (grin_core::consensus), block processing (grin_core::core::block), or any other module.
    • Risk Severity: Critical
    • Mitigation Strategies:
      • (Primarily Grin Developers): Rigorous code reviews, static analysis, fuzzing, and adherence to secure coding practices are essential to prevent such vulnerabilities.
      • (Node Operators):
        • Regular Updates: Keep the Grin node software up-to-date with the latest security patches released by the Grin developers.
        • Least Privilege: Run the Grin node as a non-privileged user to limit the damage an attacker can do if they gain control.
        • Containerization: Use a containerization technology (like Docker) to isolate the Grin node from the rest of the system, further limiting the impact of a compromise.

Threat: Kernel Excess Manipulation

  • Description: An attacker crafts an invalid transaction with a manipulated kernel excess, attempting to bypass the validation checks within the Grin node and potentially create coins out of thin air or cause other inconsistencies that violate the protocol's rules. This is a direct attack on the core transaction validation logic.
    • Impact: Could lead to inflation of the Grin supply (creating coins from nothing) or disruption of the network's consensus, potentially causing forks or other instability.
    • Affected Grin Component: grin_core::core::transaction::Transaction and the validation logic within grin_core::core::verifier_cache, and related consensus checks in grin_core::consensus. This directly targets the core cryptographic verification of transactions.
    • Risk Severity: Critical
    • Mitigation Strategies:
      • (Primarily Grin Developers):
        • Strict Kernel Validation: The Grin node implementation must rigorously enforce the rules for kernel excess validation, including checking for correct signatures and range proofs. Any flaw here is a critical vulnerability.
        • Code Audits: Regular and thorough code audits of the transaction and kernel validation code are essential to identify and fix any potential vulnerabilities.
        • Formal Verification: Consider using formal verification techniques (where feasible) to mathematically prove the correctness of the critical validation logic.