CVE-2024-34478VulnerabilityPublished 5 May 2024Updated 7 Aug 2024

CVE-2024-34478: btcd · n/a

Affects btcdSource CVE Database V5

Not known to be exploited · CVSS 7.5 High : upgrade to 0.24.0 soon.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.5% chance of exploitation in 30 days – higher than 46% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 0.24.0

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: High
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 5 May 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade btcsuite/btcd to 0.24.0.

Affected software

Product	Affected	Fixed in
GitHubbtcsuite/btcd`pkg:github/btcsuite/btcd`Other threats	Affected <0.24.0	Fixed in 0.24.0

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Organizations should immediately upgrade all btcd nodes to version 0.24.0 or later, where the consensus rule implementation correctly treats the transaction version as an unsigned integer. Until upgrades are applied, operators should monitor blockchain behavior closely for signs of chain splits or consensus anomalies. Running parallel nodes with alternative Bitcoin implementations (e.g., Bitcoin Core) can help detect discrepancies early. Network-level monitoring for unusual transaction patterns or forks can provide early warning of exploitation attempts. Operators should also ensure that their nodes are not exposed unnecessarily to untrusted networks and consider restricting RPC and P2P access to trusted peers. Regularly reviewing and applying security advisories from btcd maintainers and the broader Bitcoin community is critical. Finally, organizations should prepare incident response plans for potential chain splits or transaction rollbacks to minimize financial and operational impact.

Description

btcd before 0.24.0 does not correctly implement the consensus rules outlined in BIP 68 and BIP 112, making it susceptible to consensus failures. Specifically, it uses the transaction version as a signed integer when it is supposed to be treated as unsigned. There can be a chain split and loss of funds.

Impact

The primary impact of CVE-2024-34478 is on the integrity of the Bitcoin blockchain as maintained by btcd nodes. Consensus failures can lead to chain splits, which undermine trust in the blockchain's immutability and can cause transaction rollbacks or double-spending attacks. This threatens the reliability of financial transactions and can result in direct monetary losses for users and organizations relying on affected nodes. Additionally, chain splits can disrupt network stability and reduce confidence in the Bitcoin ecosystem. Since the vulnerability is remotely exploitable without authentication or user interaction, attackers can potentially trigger consensus failures at scale. Organizations operating btcd nodes, cryptocurrency exchanges, wallet providers, and financial institutions involved in Bitcoin transactions face significant operational and reputational risks. The absence of known exploits currently limits immediate widespread impact, but the vulnerability's nature demands urgent remediation to prevent future exploitation.

Summary

CVE-2024-34478 affects the btcd Bitcoin full node implementation prior to version 0.24.0. The vulnerability stems from an incorrect handling of the transaction version field during consensus rule enforcement as defined in Bitcoin Improvement Proposals (BIPs) 68 and 112. Specifically, btcd treats the transaction version as a signed integer, whereas the Bitcoin protocol requires it to be interpreted as an unsigned integer. This discrepancy can cause the node to accept or reject transactions inconsistently compared to other compliant nodes, leading to consensus failures. Such failures can manifest as chain splits, where different nodes disagree on the canonical blockchain state. Chain splits can cause transaction rollbacks, double-spending, and ultimately loss of funds for users relying on the affected nodes. The vulnerability is remotely exploitable without authentication or user interaction, increasing its risk profile. Although no active exploits are currently known, the potential for disruption in blockchain consensus and financial loss is substantial. The issue is categorized under CWE-436 (Improper Handling of Critical Data). No official patches are linked yet, but upgrading to btcd 0.24.0 or later is advised to resolve the problem.

CWE-436Interpretation Conflict (opens in a new tab)
Class weaknessOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
Product A handles inputs or steps differently than Product B, which causes A to perform incorrect actions based on its perception of B's state.
OWASP Cheat Sheets
REST Assessment (opens in a new tab)
REST Security (opens in a new tab)
Cross-Site Request Forgery Prevention (opens in a new tab)
Secure Design Principles (opens in a new tab)
OWASP ASVS 4.0.3
V13.2.5 (opens in a new tab)
Attack patterns
HTTP Request Splitting (opens in a new tab)
HTTP Response Smuggling (opens in a new tab)
HTTP Response Splitting (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 4 Mar 2026, 23:19 UTC

WeaknessesCWE-436

Technical details

References

Community reviews

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