The hardware implant found in CryptoBilis-sold Ledger wallets decoded recovery phrases from the device screen and transmitted them over cellular networks using an embedded eSIM.

From the articleTrezor: No Reports of Tampered Devices, But Will Restrict Some ResellersAlso in Trezor trims its reseller network after Ledger supply-chain attack, Ledger's crypto wallet implant scare triggers Trezor reseller crackdown as security fears spread, Trezor Cuts Its Resellers After Ledger Finds Spy Implant in Crypto Wallets - Decrypt, Trezor Cuts Ties With Resellers After Major Ledger Security Scare - U.Today, Trezor Wallet Takes Drastic Supply-Chain Action To Increase Security, Trezor Reduces Number Of Resellers Following Ledger Incident, Trezor shrinks reseller network, exposing crypto's supply-chain weak spot - Cryptopolitan