CVE-2021-31876
Published May 13, 2021
Last updated 3 years ago
Overview
- 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.
- Source
- cve@mitre.org
- NVD status
- Analyzed
Risk scores
CVSS 3.1
- Type
- Primary
- Base score
- 6.5
- Impact score
- 2.5
- Exploitability score
- 3.9
- Vector string
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
- Severity
- MEDIUM
CVSS 2.0
- Type
- Primary
- Base score
- 6.4
- Impact score
- 4.9
- Exploitability score
- 10
- Vector string
- AV:N/AC:L/Au:N/C:N/I:P/A:P
Weaknesses
- nvd@nist.gov
- CWE-863
Social media
- Hype score
- Not currently trending
Configurations
[
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:bitcoin:bitcoin:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "6042CD5C-8EC2-4CE6-A588-DC76F6A001B0",
"versionEndIncluding": "0.21.1",
"versionStartIncluding": "0.12.0"
}
],
"operator": "OR"
}
]
}
]