CVE-2021-31876

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.

CVSS v3.0 6.5 MEDIUM
CVSS v2.0 6.4 MEDIUM

6.5^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

6.4^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:N/I:P/A:P

Exploitability : 10.0 / Impact : 4.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

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

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Configurations

Configuration 1 (hide)

cpe:2.3:a:bitcoin:bitcoin:*:*:*:*:*:*:*:*

Information

Published : 2021-05-13 15:15

Updated : 2021-05-26 13:12

NVD link : CVE-2021-31876

Mitre link : CVE-2021-31876

JSON object : View

CWE

CWE-863

Incorrect Authorization

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Products Affected

bitcoin

bitcoin

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