CVE-2025-66017 in cggmp21
Summary
by MITRE • 11/25/2025
CGGMP24 is a state-of-art ECDSA TSS protocol that supports 1-round signing (requires 3 preprocessing rounds), identifiable abort, and a key refresh protocol. In versions 0.6.3 and prior of cggmp21 and version 0.7.0-alpha.1 of cggmp24, presignatures can be used in the way that significantly reduces security. cggmp24 version 0.7.0-alpha.2 release contains API changes that make it impossible to use presignatures in contexts in which it reduces security.
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Analysis
by VulDB Data Team • 11/27/2025
The CVE-2025-66017 vulnerability affects the CGGMP24 threshold signature scheme, a sophisticated elliptic curve digital signature algorithm implementation designed for distributed security scenarios. This protocol represents an advanced evolution of the original CGGMP21 specification, incorporating state-of-the-art features including one-round signing capabilities that require only three preprocessing rounds, identifiable abort mechanisms for fault detection, and key refresh protocols for ongoing security maintenance. The vulnerability specifically targets the presignature generation and utilization mechanisms within the cryptographic protocol stack.
The technical flaw stems from improper handling of presignature usage patterns in versions 0.6.3 and prior of cggmp21 and version 0.7.0-alpha.1 of cggmp24. Presignatures in threshold signature schemes are precomputed partial signatures that enable rapid signature generation when the actual signing operation occurs. However, the vulnerability allows for presignatures to be employed in contexts where their reuse or improper generation creates significant security degradation. This represents a critical flaw in the protocol's design that violates fundamental cryptographic security principles, as the vulnerability enables scenarios where attackers could potentially compromise the entire threshold signature system through manipulation of presignature generation processes.
The operational impact of this vulnerability extends beyond simple cryptographic weakness to encompass broader security implications for any system relying on these threshold signature implementations. Attackers could exploit this flaw to perform unauthorized signature operations or potentially gain information about the underlying secret shares within the threshold scheme. The vulnerability particularly affects systems implementing multi-party computation protocols where multiple parties must collaborate to generate valid signatures without any single party possessing the complete private key. This creates a significant risk for financial institutions, blockchain networks, and other security-critical applications that depend on robust threshold signature schemes for their operations.
The security implications align with CWE-310 (Cryptographic Issues) and represent a specific instance of improper cryptographic implementation that violates the principle of least privilege in threshold signature schemes. The vulnerability also maps to ATT&CK technique T1587.001 (Development Tools: Compromise Software Supply Chain) when considering potential supply chain impacts, though the primary threat vector lies in the protocol's design rather than external compromise. The fix implemented in cggmp24 version 0.7.0-alpha.2 addresses the issue through API changes that prevent the insecure usage patterns, effectively eliminating the attack surface by restricting how presignatures can be generated and utilized within the system.
Organizations utilizing these threshold signature implementations should immediately upgrade to cggmp24 version 0.7.0-alpha.2 or later, as the API changes represent a breaking modification that prevents the vulnerable presignature usage patterns. Security teams should conduct thorough audits of systems relying on these protocols to identify any remaining instances of the vulnerable versions and ensure complete remediation across all operational environments. The vulnerability demonstrates the critical importance of proper cryptographic protocol design and the necessity of rigorous security testing for threshold signature schemes, particularly in high-security applications where cryptographic failures can result in complete system compromise.