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).
6.5.4~dfsg-16.5.4~dfsg-26.5.7+dfsg-16.6.1+dfsg-16.5.4~dfsg-26.5.7+dfsg-16.6.1+dfsg-16.6.1+dfsg-16.6.1+dfsg-1Exploitability
AV:NAC:HPR:NUI:NScope
S:UImpact
C:LI:LA:LCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L