exploit
Trezor warns Safe 5 units sold by CryptoBilis carry a cellular implant
Trezor says a Safe 5 bought on Tokopedia from reseller CryptoBilis carried an extra PCB with a cellular module that reads the screen and leaks the seed. Trezor cut ties with the reseller Oct 9.
Czech hardware-wallet maker Trezor is advising every customer who bought a device from Southeast Asian reseller CryptoBilis since March 2026 to move funds to a new wallet with a freshly generated seed on a trusted device. The warning follows a responsible disclosure from an Indonesian customer who found an extra circuit board carrying a cellular module and antenna wedged between the main board and the screen of a Safe 5 bought on Tokopedia in August 2026.
What happened
The Indonesian customer disclosed the finding to Trezor on Oct 28, 2026. Per the customer's report — Trezor has not yet physically examined the device — the implant sits between the mainboard and the display, reads whatever is rendered on the screen (including the recovery-seed words shown during setup or recovery), and exfiltrates them over a mobile-network connection when the device is powered. Trezor Chief Commercial Officer Danny Sanders told The Block the company is treating the report as credible: "we'd rather warn people now than wait for confirmation and find out someone lost their funds in the meantime."
Trezor had already removed CryptoBilis from its authorized-reseller list on Oct 9, after the first signs of trouble on the Ledger side (see context below). Devices Trezor had already pulled from CryptoBilis — one Safe 7, two Safe 5 units, one Safe 3 — showed no tampering under inspection. The newly disclosed Safe 5 was not among them.
Mechanism — reading the screen, not the chip
The implant does not need to touch the secure element. Modern hardware wallets show the seed on the device screen during initial setup and recovery, precisely so the host computer never sees it. A board that intercepts the display line can snapshot the words in the clear, then relay them. The cellular path means the implant can leak the seed even when the device is only ever connected to a victim's air-gapped laptop — the host network does not see the exfiltration.
Trezor's immediate guidance:
- Any device from CryptoBilis purchased since March 2026: do not use. Trezor is offering replacements or vouchers.
- If already set up: assume the seed is compromised. Create a new wallet on a different, trusted device, generate a new seed, and move funds there. Do not reuse the old seed.
- Unopened units: do not initialize.
On-chain trail — the Ledger side
The report sits inside a larger pattern. Ledger opened its own investigation into CryptoBilis-sold units on the same day — Oct 9 — after confirmed physical tampering was reported in CryptoBilis-branded Ledgers. Chainalysis reports losses tied to those tampered Ledgers at more than 60 BTC (roughly $4.8M), per the Decrypt walkthrough. Separately, Arkham traced about $95.35M across 1,486 addresses that researchers suspect are tied to the reseller's channel — a figure Ledger has not confirmed. Rival maker OneKey has also cut ties with CryptoBilis.
Numbers block
- At-risk device window: all Trezor models bought from CryptoBilis since March 2026.
- Devices Trezor has pulled and inspected: 4 (1 Safe 7, 2 Safe 5, 1 Safe 3) — no tampering found.
- Trezor losses linked to CryptoBilis Trezors: none reported.
- Ledger losses linked to CryptoBilis Ledgers: >60 BTC (~$4.8M), per Chainalysis.
- Suspected addresses in Arkham's wider sweep: 1,486, holding roughly $95.35M; unconfirmed by Ledger.
- Trezor reseller status for CryptoBilis: removed on Oct 9, 2026.
What to watch
- Trezor's forensic report on the disclosed Safe 5. The implant description comes from the finder, not from Trezor's own lab yet.
- Mobile-carrier traces from any confirmed implanted units — the attacker needs a SIM and a backend to receive seeds, both of which leave records.
- Other Southeast-Asian resellers on Tokopedia, Lazada and Shopee. The CryptoBilis storefront is one of many.
- A manufacturer response at the physical-security layer — a tamper-evident display assembly or a signed-boot screen attestation would raise the bar on this class of attack.
Context — hardware-wallet supply-chain attacks move Southeast
Supply-chain tampering of signing devices is a known threat model: Trezor and Ledger both warn customers to buy only from the manufacturer or audited resellers for exactly this reason. What is new is the operational scale. In the span of three weeks, two of the three biggest hardware-wallet makers have confirmed tampered units reaching customers through a single Southeast-Asian storefront, with a third (OneKey) following suit. The attack bypasses the usual threat model of key extraction from the secure element by targeting the display line instead — a route the current generation of consumer hardware does not defend.