CVE-2021-31876
Bitcoin Core Reversible Replacement Policy Denial of Service
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.
INFO
Published Date :
May 13, 2021, 10:15 p.m.
Last Modified :
May 26, 2021, 8:12 p.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
2.5
Exploitability Score :
3.9
Public PoC/Exploit Available at Github
CVE-2021-31876 has a 1 public PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-31876.
| URL | 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 |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
master
C++ HTML M4
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-31876 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-31876 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Initial Analysis by [email protected]
May. 26, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:N/I:P/A:P) Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L Changed Reference Type https://bitcoinops.org/en/newsletters/2021/05/12/ No Types Assigned https://bitcoinops.org/en/newsletters/2021/05/12/ Vendor Advisory Changed Reference Type https://bitcoinops.org/en/topics/replace-by-fee/ No Types Assigned https://bitcoinops.org/en/topics/replace-by-fee/ Vendor Advisory Changed Reference Type https://en.bitcoin.it/wiki/Common_Vulnerabilities_and_Exposures#CVE-2021-31876 No Types Assigned https://en.bitcoin.it/wiki/Common_Vulnerabilities_and_Exposures#CVE-2021-31876 Third Party Advisory Changed Reference Type https://github.com/bitcoin/bitcoin No Types Assigned https://github.com/bitcoin/bitcoin Third Party Advisory Changed Reference Type https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2021-May/018893.html No Types Assigned https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2021-May/018893.html Mailing List, Third Party Advisory Added CWE NIST CWE-863 Added CPE Configuration OR *cpe:2.3:a:bitcoin:bitcoin:*:*:*:*:*:*:*:* versions from (including) 0.12.0 up to (including) 0.21.1
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-31876 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-31876
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.16 }} 0.02%
score
0.53140
percentile