CVE-2026-55174 (GCVE-0-2026-55174)

Vulnerability from cvelistv5 – Published: 2026-09-30 15:49 – Updated: 2026-09-30 15:49
VLAI
Title
UltrafastSecp256k1: ECDSA adaptor verification accepts non-adaptable pre-signatures due to missing DLEQ binding
Summary
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.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE
  • CWE-345 - Insufficient Verification of Data Authenticity
  • CWE-347 - Improper Verification of Cryptographic Signature
Assigner
References
Impacted products
Vendor Product Version CPE status
shrec UltrafastSecp256k1 Affected: < 4.2.0
guessed Create a notification for this product.
Show details on NVD website
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        }
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      "title": "UltrafastSecp256k1: ECDSA adaptor verification accepts non-adaptable pre-signatures due to missing DLEQ binding"
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    "dateReserved": "2026-06-16T15:20:43.085Z",
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          }
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        "metrics": {
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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