CVE-2026-55174

UltrafastSecp256k1 is a high-performance, multi-backend secp256k1 engine with reproducible audit evidence, compatibility shims, and profile-based review scopes. Prior to version 4.2.0, UltrafastSecp256k1's ECDSA adaptor pre-signature verification accepts forged adaptor pre-signatures whose "r" value is not cryptographically bound to the adaptor point "T". This issue has been patched in version 4.2.0.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/shrec/UltrafastSecp256k1/commit/5478ef566c6af91b48a45c0c61f161f5b1071981
https://github.com/shrec/UltrafastSecp256k1/releases/tag/v4.2.0
https://github.com/shrec/UltrafastSecp256k1/releases/tag/v4.2.1
https://github.com/shrec/UltrafastSecp256k1/security/advisories/GHSA-c7q2-gv3g-rgxm
https://github.com/shrec/UltrafastSecp256k1/security/advisories/GHSA-c7q2-gv3g-rgxm

Configurations

No configuration.

History

30 Sep 2026, 20:17

Type	Values Removed	Values Added
References	~~() https://github.com/shrec/UltrafastSecp256k1/security/advisories/GHSA-c7q2-gv3g-rgxm -~~	() https://github.com/shrec/UltrafastSecp256k1/security/advisories/GHSA-c7q2-gv3g-rgxm -

30 Sep 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-30 16:17

Updated : 2026-09-30 20:17

NVD link : CVE-2026-55174

Mitre link : CVE-2026-55174

CVE.ORG link : CVE-2026-55174

JSON object : View

Products Affected

No product.

CWE

CWE-345

Insufficient Verification of Data Authenticity

CWE-347

Improper Verification of Cryptographic Signature

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