CVE-2021-31876
CVSS V2 Medium 6.4
CVSS V3 Medium 6.5
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.
Overview
- CVE ID
- CVE-2021-31876
- Assigner
- cve@mitre.org
- Vulnerability Status
- Analyzed
- Published Version
- 2021-05-13T22:15:07
- Last Modified Date
- 2021-05-26T20:12:00
Weakness Enumerations
CPE Configuration (Product)
| CPE | Vulnerable | Operator | Version Start | Version End |
|---|---|---|---|---|
| cpe:2.3:a:bitcoin:bitcoin:*:*:*:*:*:*:*:* | 1 | OR | 0.12.0 | 0.21.1 |
CVSS Version 2
- Version
- 2.0
- Vector String
- AV:N/AC:L/Au:N/C:N/I:P/A:P
- Access Vector
- NETWORK
- Access Compatibility
- LOW
- Authentication
- NONE
- Confidentiality Impact
- NONE
- Integrity Impact
- PARTIAL
- Availability Impact
- PARTIAL
- Base Score
- 6.4
- Severity
- MEDIUM
- Exploitability Score
- 10
- Impact Score
- 4.9
CVSS Version 3
- Version
- 3.1
- Vector String
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
- Attack Vector
- NETWORK
- Attack Compatibility
- LOW
- Privileges Required
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality Impact
- NONE
- Availability Impact
- LOW
- Base Score
- 6.5
- Base Severity
- MEDIUM
- Exploitability Score
- 3.9
- Impact Score
- 2.5
References
| Reference URL | Reference Tags |
|---|---|
| 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 |
Sources
| Source Name | Source URL |
|---|---|
| NIST | https://nvd.nist.gov/vuln/detail/CVE-2021-31876 |
| MITRE | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-31876 |
History
| Created | Old Value | New Value | Data Type | Notes |
|---|---|---|---|---|
| 2022-05-10 16:14:35 | Added to TrackCVE | |||
| 2022-12-05 02:15:52 | 2021-05-13T22:15Z | 2021-05-13T22:15:07 | CVE Published Date | updated |
| 2022-12-05 02:15:52 | 2021-05-26T20:12:00 | CVE Modified Date | updated | |
| 2022-12-05 02:15:52 | Analyzed | Vulnerability Status | updated |