Here’s what happened in crypto today

Today in crypto, Trezor is reducing its authorized reseller network after reports of tampered Ledger wallets, MediaMarktSaturn pulled Ledger products from stores and online platforms and Aptos launched an encrypted transaction feature to protect traders from frontrunning and sandwich attacks.

Trezor cuts reseller network after Ledger wallet tampering reports

Hardware wallet maker Trezor is reducing its authorized reseller network after reports that a Southeast Asian reseller modified Ledger devices to steal users’ recovery phrases.

Trezor said Tuesday the decision was precautionary and that it had no evidence its own devices were compromised. Chief commercial officer Danny Sanders said affected resellers would lose their authorized status on Jan. 1, with shipments to those businesses stopping immediately.

The move follows rival Ledger’s confirmation that at least one device sold by reseller CryptoBilis contained an unauthorized hardware implant capable of capturing recovery phrases and transmitting them over cellular networks.

The incident has raised questions about the security of hardware wallet supply chains. Trezor told Cointelegraph that its existing checks can detect counterfeit devices and modified firmware, but the Ledger implant operated differently by reading information displayed on the device’s screen.

Blockchain investigators have estimated potential losses of between $72 million and $86 million, although Ledger said it had not confirmed the total.

Trezor advised customers to purchase devices directly from the manufacturer and consider multisignature wallets using hardware from different providers.

MediaMarktSaturn pulls Ledger products amid tampering reports

MediaMarktSaturn, the parent company of European electronics retailer MediaMarkt, has removed Ledger products from its physical stores and online platforms amid reports of tampered hardware wallets.

“The products have been removed from our product lineup internationally in all of our countries. We did this as a precautionary measure,” a MediaMarktSaturn spokesperson told Cointelegraph.

Ledger said Tuesday that MediaMarktSaturn suspended sales in coordination with the wallet maker following a report of a hardware implant from a customer in Germany. Ledger said no fund losses had been reported in connection with that case and that it had no indication its infrastructure, systems or services were compromised.

An X user known as Johannes claimed Monday that he purchased two Ledger wallets from separate MediaMarkt stores. He said both contained unauthorized cables and cellular modules.

The security concerns emerged Friday after Ledger said it is investigating reports of losses involving devices sold through Southeast Asian reseller CryptoBilis. Ledger said Tuesday that implants transmitted users’ recovery phrases over cellular networks and that it was investigating reports beyond CryptoBilis.

Aptos rolls out Encrypted Mempool to curb frontrunning, sandwich attacks

Layer-1 blockchain Aptos has launched an optional new feature that could help shield traders from attacks involving maximal extractable value (MEV), including frontrunning and sandwich attacks. 

On Monday, Aptos said its Encrypted Mempool feature is now live on its mainnet, allowing users to opt in to keep pending transactions encrypted until their block ordering is finalized. Aptos said the feature was built for institutions submitting large transactions to the chain, traders wanting to avoid MEV risk, AI agents and builders. 

“When you send a transaction on any major chain today, anyone watching the network can see the details before it executes, the function you’re calling, the assets and amounts involved, and the contracts you’re interacting with,” Aptos said. “Bots use that visibility to trade against you or copy your strategy.”  

Sandwich attacks, one form of MEV attack, cost Ethereum traders about $60 million over the 12 months through October 2025, according to Cointelegraph’s analysis of EigenPhi data. On Solana, sandwich attacks generated $29.7 million for bots over an 11-month period examined by Bitquery, which identified nearly 6.9 million attacks affecting about 2.2 million wallets.