Fund loss or service interruption via RBF mismatch
Published May 13, 2021 · Updated Aug 3, 2024
Transaction replacement policy flaw in Bitcoin Core 0.12.0 through 0.21.1 allows remote attackers to cause fund loss or service interruption. MemPoolAccept::PreChecks ignores BIP125 inherited replaceability when an unconfirmed child uses final nSequence, so the mempool rejects its replacement. Exploitation depends on a downstream protocol such as Lightning relying on inherited replacement; the mismatch makes an existing transaction-pinning attack cheaper.
Summary
What happened
Transaction replacement policy flaw in Bitcoin Core 0.12.0 through 0.21.1 allows remote attackers to cause fund loss or service interruption. MemPoolAccept::PreChecks ignores BIP125 inherited replaceability when an unconfirmed child uses final nSequence, so the mempool rejects its replacement. Exploitation depends on a downstream protocol such as Lightning relying on inherited replacement; the mismatch makes an existing transaction-pinning attack cheaper.
The record
- CVE
- CVE-2021-31876
- Published
- May 13, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-863, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 13, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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