UnratedGoPublished
Taurus multi-party-sig has OT-based ECDSA protocol implementation flaws
GHSA-7f6p-phw2-8253
- Affected
- Go github.com/taurusgroup/multi-party-sig <= 0.6.0-alpha-2021-09-21
- Fixed in
- 0.7.0-alpha-2025-01-28· Vendor fix available
- Issue
- Coinbase researchers reported 2 security issues in our implementation of the oblivious transfer (OT) based protocol DKLS: 1. Secret share recovery attack If the base OT setup of the protocol is reused for another execution of the OT extension, then a malicious participant can extract a bit of the secret of another participant. By repeating the execution they can eventually recover the whole secret. Therefore, unlike our comments suggested, you must not reuse an OT setup for multiple protocol executions. We're adding a warning in the code: https://github.com/taurushq-io/multi-party-sig/blob/9e4400fccee89be6195d0a12dd0ed052288d5040/internal/ot/extended.go#L114 2. Invalid security proof due to incorrect operator The original 2018 version of the DKLS had a typo in the OT extension protocol when computing the check value in the OT extension: the paper noted a XOR whereas it should be a field multiplication. This erroneous behavior was implemented in our code. The proof of security fails…
Recommended action: Upgrade to 0.7.0-alpha-2025-01-28 (pre-release) or later, then redeploy and verify.A vendor fix does not resolve your finding until you verify it in your own systems.