CVE-2026-3194 in Blockchain
Summary
by MITRE • 02/25/2026
A flaw has been found in Chia Blockchain 2.1.0. The affected element is the function send_transaction/get_private_key of the component RPC Server Master Passphrase Handler. This manipulation causes missing authentication. The attack can only be executed locally. The attack's complexity is rated as high. The exploitability is described as difficult. The exploit has been published and may be used. The vendor was informed early via email. A separate report via bugbounty was rejected with the reason "This is by design. The user is responsible for host security".
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Analysis
by VulDB Data Team • 03/06/2026
The vulnerability identified as CVE-2026-3194 resides within the Chia Blockchain 2.1.0 implementation, specifically targeting the RPC Server Master Passphrase Handler component. This flaw manifests through the send_transaction and get_private_key functions, which are critical operational elements for blockchain transaction processing and private key management. The vulnerability represents a significant security oversight as it fundamentally undermines the authentication mechanisms that should protect sensitive cryptographic operations within the blockchain infrastructure.
The technical implementation of this vulnerability stems from insufficient authentication checks within the RPC server's master passphrase handler. When users attempt to execute transaction operations or retrieve private keys through the affected functions, the system fails to properly validate user credentials or authorization levels. This authentication bypass allows malicious actors to perform sensitive operations without proper verification, creating a dangerous exposure in the blockchain's security architecture. The flaw operates at the application layer and specifically affects the RPC server's handling of passphrase-based authentication mechanisms.
The operational impact of this vulnerability is severe despite its local execution requirement. While the attack vector is limited to local system access, the implications are profound for any system where the Chia blockchain software operates with elevated privileges. An attacker with local access can potentially execute unauthorized transactions, extract private keys, or manipulate blockchain data without proper authorization. This creates a significant risk for system administrators, developers, and users who rely on the Chia blockchain for financial or data integrity purposes. The vulnerability essentially removes the authentication barrier that should protect sensitive cryptographic operations from unauthorized access.
The complexity rating of high and exploitability difficulty indicates that while this vulnerability requires specific local system access and technical knowledge to exploit, the potential damage is substantial. The fact that the exploit has been published and may be used in the wild demonstrates that the vulnerability is not merely theoretical but represents an active threat to systems running the affected Chia Blockchain version. The vendor's response, which dismissed the report by designating it as user responsibility for host security, raises concerns about the security posture of the blockchain implementation and suggests that the system may not adequately protect against local privilege escalation attacks.
This vulnerability aligns with CWE-287, which addresses improper authentication issues in software systems, and relates to ATT&CK techniques such as privilege escalation and credential access. The local execution requirement places this vulnerability in the context of lateral movement and host-based attacks rather than network-based exploits. Organizations should consider implementing additional host security measures including proper access controls, monitoring for unauthorized RPC activity, and ensuring that only authorized personnel have local system access to Chia blockchain installations. The incident highlights the critical importance of proper authentication mechanisms in cryptocurrency systems where unauthorized access could result in complete financial loss and data compromise.