cve/2023/CVE-2023-26557.md

### [CVE-2023-26557](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-26557)
![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brighgreen)

### Description

io.finnet tss-lib before 2.0.0 can leak the lambda value of a private key via a timing side-channel attack because it relies on Go big.Int, which is not constant time for Cmp, modular exponentiation, or modular inverse. An example leak is in crypto/paillier/paillier.go. (bnb-chain/tss-lib and thorchain/tss are also affected.)

### POC

#### Reference
- https://medium.com/@iofinnet/security-disclosure-for-ecdsa-and-eddsa-threshold-signature-schemes-4e969af7155b

#### Github
No PoCs found on GitHub currently.