Vulnerability in Btcd Project
CVE-2024-38365
btcd is an alternative full node bitcoin implementation written in Go (golang). The btcd Bitcoin client (versions 0.10 to 0.24) did not correctly re-implement Bitcoin Core's "FindAndDelete()" functionality. This logic is consensus-critical: the difference in behavior with the other Bitcoin clients can lead to btcd clients accepting an invalid Bitcoin block (or rejecting a valid one). This consensus failure can be leveraged to cause a chain split (accepting an invalid Bitcoin block) or be exploited to DoS the btcd nodes (rejecting a valid Bitcoin block). An attacker can create a standard transaction where FindAndDelete doesn't return a match but removeOpCodeByData does making btcd get a different sighash, leading to a chain split. Importantly, this vulnerability can be exploited remotely by any Bitcoin user and does not require any hash power. This is because the difference in behavior can be triggered by a "standard" Bitcoin transaction, that is a transaction which gets relayed through the P2P network before it gets included in a Bitcoin block. `removeOpcodeByData(script []byte, dataToRemove []byte)` removes any data pushes from `script` that contain `dataToRemove`. However, `FindAndDelete` only removes exact matches. So for example, with `script = "<data> <data||foo>"` and `dataToRemove = "data"` btcd will remove both data pushes but Bitcoin Core's `FindAndDelete` only removes the first `<data>` push. This has been patched in btcd version v0.24.2. Users are advised to upgrade. There are no known workarounds for this issue.
EPSS: 0.010 (59.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H.
Affected products
- Btcd_project Btcd
- Btcsuite Btcd — versions >= 0.10.0, < 0.24.2
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC, Issue Tracking)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2024-38365?
- CVE-2024-38365 is a high-severity vulnerability in Btcd Project, classified under Always-Incorrect Control Flow Implementation. CVSS score: 7.4/10. Published 2024-10-11.
- How severe is CVE-2024-38365?
- High severity. CVSS v3 base score is 7.4 out of 10.
- Is CVE-2024-38365 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.