Description
ZF FROST is a Rust implementation of FROST (Flexible Round-Optimised Schnorr Threshold signatures). In versions 2.0.0 through 2.1.0, refresh shares with smaller min_signers will reduce security of group. The inability to change min_signers (i.e. the threshold) with the refresh share functionality (frost_core::keys::refresh module) was not made clear to users. Using a smaller value would not decrease the threshold, and attempts to sign using a smaller threshold would fail. Additionally, after refreshing the shares with a smaller threshold, it would still be possible to sign with the original threshold, potentially causing a security loss to the participant's shares. This issue is fixed in version 2.2.0.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
ZcashFoundation frost
>= 2.0.0, < 2.2.0affected