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CVE-2021-31876 Detail

Current Description

Bitcoin Core 0.12.0 through 0.21.1 does not properly implement the replacement policy specified in BIP125, which makes it easier for attackers to trigger a loss of funds, or a denial of service attack against downstream projects such as Lightning network nodes. An unconfirmed child transaction with nSequence = 0xff_ff_ff_ff, spending an unconfirmed parent with nSequence <= 0xff_ff_ff_fd, should be replaceable because there is inherited signaling by the child transaction. However, the actual PreChecks implementation does not enforce this. Instead, mempool rejects the replacement attempt of the unconfirmed child transaction.


View Analysis Description

Severity



CVSS 3.x Severity and Metrics:

NIST CVSS score
NIST: NVD
Base Score:  6.5 MEDIUM
Vector:  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: NVD Analysts have published a CVSS score for this CVE based on publicly available information at the time of analysis. The CNA has not provided a score within the CVE List.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://bitcoinops.org/en/newsletters/2021/05/12/ Vendor Advisory 
https://bitcoinops.org/en/topics/replace-by-fee/ Vendor Advisory 
https://en.bitcoin.it/wiki/Common_Vulnerabilities_and_Exposures#CVE-2021-31876 Third Party Advisory 
https://github.com/bitcoin/bitcoin Third Party Advisory 
https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2021-May/018893.html Mailing List  Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-863 Incorrect Authorization cwe source acceptance level NIST  

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Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-31876
NVD Published Date:
05/13/2021
NVD Last Modified:
05/26/2021
Source:
MITRE