Trezor Safe 3, Safe 5, and Safe 7 firmware contains a confirmation-binding flaw in the Ethereum sign_tx / sign_tx_eip1559 flow. For contract interactions, the device confirms only the initial calldata chunk while the signature commits to the full streamed calldata. An attacker could present calldata to a victim then supply a different tail that changes the signed transaction. Fixed in 70c9b0c.
Trezor Safe 3, Safe 5, and Safe 7 firmware contains a confirmation-binding flaw in the Ethereum sign_tx / sign_tx_eip1559 flow. For contract interactions, the device confirms only the initial calldata chunk while the signature commits to the full streamed calldata. An attacker could present calldata to a victim then supply a different tail that changes the signed transaction. Fixed in 70c9b0c.
Why this VPI (explainable, experimental)
VPI breakdown
| Impact | 59.00 |
| Exploitation signal(No additional exploitation signal) | ×1.00 |
| VPI | 59.00 |
VPI formula vpi-v1
| Source | CVSS Version | Base Score | Severity | Vector String | Assessment Date |
|---|---|---|---|---|---|
| NVDNIST | 4.0 | 5.9 | MEDIUM | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X | 07/22/2026 |
| NVDNIST |
| 3.1 |
| 5.3 |
MEDIUM |
| CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N |
| 07/22/2026 |