CVE-2021-31876 Business logic in n/a
Bitcoin Core fails to enforce BIP125 replacement rules, allowing attackers to cause denial of service or loss of funds in downstream projects.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-31876?
CVE-2021-31876 is a medium-severity vulnerability in n/a, published on 13 May 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-863
Which versions are affected by CVE-2021-31876?
It affects 1 product.
Products include Bitcoin Bitcoin.
How do I fix CVE-2021-31876?
No fix has been published for CVE-2021-31876 yet. Limit exposure of the affected software until one is available.
Is CVE-2021-31876 being exploited?
There is no known exploitation of CVE-2021-31876 in the wild and no public exploit code.
Other vulnerabilities in n/a
Sources
Also known as GHSA-cm2c-8c7c-974f.