According to CoinMeta, Ledger's Chief Technology Officer Charles Guillemet tweeted that there was a vulnerability in the plaintext signing process of the Ethereum application part of Ledger. This vulnerability was discovered by Ledger Donjon using the AI vulnerability research tool and was fixed and deployed two weeks ago. Users who have kept their Ledger firmware and application updates are not affected. Guillemet stated that an organization claiming to be "smart contract security" contacted the vulnerability bounty program after the fix was made, without following the responsible disclosure process, and then released content implying that the vulnerability had not been resolved.