CVE-2025-14505

Elliptic Cryptanalysis vulnerability when `k` has leading zeros

MEDIUM
5.6
CVSS Score
Published: January 8, 2026 at 09:05 PM UTC
Updated: June 17, 2026 at 08:36 AM UTC
1 product affected across 1 vendorElliptic

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Severity
MEDIUM5.6
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

The ECDSA implementation of the Elliptic package generates incorrect signatures if an interim value of 'k' (as computed based on step 3.2 of RFC 6979 https://datatracker.ietf.org/doc/html/rfc6979 ) has leading zeros and is susceptible to cryptanalysis, which can lead to secret key exposure. This happens, because the byte-length of 'k' is incorrectly computed, resulting in its getting truncated during the computation. Legitimate transactions or communications will be broken as a result. Furthermore, due to the nature of the fault, attackers could–under certain conditions–derive the secret key, if they could get their hands on both a faulty signature generated by a vulnerable version of Elliptic and a correct signature for the same inputs. This issue affects all known versions of Elliptic (at the time of writing, versions less than or equal to 6.6.1).

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (2)

Issue TrackingExploit
Source: 36c7be3b-2937-45df-85ea-ca7133ea542c
https://github.com/indutny/elliptic/issues/321
Third Party Advisory
Source: 36c7be3b-2937-45df-85ea-ca7133ea542c
https://www.herodevs.com/vulnerability-directory/cve-2025-14505

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.6MEDIUMHeroDevs
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
LOW
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-1240

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