# Trezor Phishing Attack Bypasses Security Checks via Compromised Email Provider > A sophisticated Trezor phishing email bypassed security checks using a compromised third-party provider. Learn how to protect your hardware wallet recovery phrase. - Canonical URL: https://coreiten.com/en/article/trezor-phishing-attack-bypasses-security-checks-via-compromised-email-provider - Language: en - Section: Tech Pedia - Author: Sami - Published: 2026-09-14T10:02:54+03:00 - Modified: 2026-09-14T10:02:54+03:00 - Publisher: CoreITen (https://coreiten.com) - Keywords: Trezor phishing email, STM32, BitBox, ShipMonk, Ledger, Coldcard, hardware wallet ## Summary Trezor users are facing a sophisticated phishing campaign sent from official email domains due to a compromised third-party newsletter provider. - The malicious emails feature a fabricated warning titled 'Critical Security Alert: STM32 Entropy Vulnerability' about a hardware defect. - Trezor confirmed its devices generate at least 128-bit entropy by default, debunking the hardware flaw claims. - Attackers referenced a real Coldcard firmware flaw that caused over $130 million in stolen Bitcoin to make the scam look believable. - Swiss hardware wallet maker BitBox reported receiving an identical phishing email, suggesting multiple Bitcoin companies share the same compromised platform. - A September 4 breach at Trezor's shipping provider, ShipMonk, exposed personal data of about 67,000 additional customers, totaling nearly 80,000 affected. **Why it matters:** This incident highlights how supply chain vendors have become the new attack vector, rendering traditional email verification methods obsolete for crypto security. --- Hardware wallet users are facing a highly sophisticated phishing campaign that bypasses standard security checks by originating directly from Trezor's official email domain. The malicious "Critical Security Alert: STM32 Entropy Vulnerability" emails are designed to panic users into surrendering their recovery phrases, exploiting a compromised third-party newsletter provider rather than a flaw in the wallets themselves. The phishing email successfully bypassed spam filters and authentication protocols because it was sent through Trezor's legitimate mailing infrastructure. It falsely claimed that engineers discovered a hardware defect in the STM32 microcontrollers used in the devices, alleging that one in four wallets suffered from insufficient randomness. Trezor has confirmed this claim is entirely fabricated, noting that its devices generate at least 128-bit entropy by default. The attackers leveraged recent industry anxiety to make the threat seem credible, specifically referencing a real Coldcard firmware flaw that led to over $130 million in stolen Bitcoin earlier this year. Casa co-founder Nick Neuman and chief security officer Jameson Lopp warned that the messages did not resemble ordinary spoofing, with Neuman noting that "it's likely that a marketing email provider was compromised." > Our third-party e-mail provider has been breached. Please be aware that the email named 'Critical Security Alert: STM32 Entropy Vulnerability' is not coming from us, and it's a phishing attempt. > > - Trezor The breach appears to extend beyond a single company, pointing to a broader supply chain vulnerability. Swiss hardware wallet maker [BitBox](https://x.com/BitBoxSwiss) reported an almost identical phishing email reaching its subscribers on the same day. BitBox's preliminary review suggested that multiple Bitcoin companies share the same compromised newsletter platform. This incident follows closely on the heels of a September 4 breach at Trezor's shipping provider, ShipMonk, which exposed the personal data of around 67,000 additional customers, bringing the total affected to nearly 80,000. Similar third-party leaks have recently hit the sector, including a Ledger customer data exposure via Global-e and a Pocket Bitcoin breach affecting over 5,400 users. ### How to Secure Your Hardware Wallet Because the phishing emails originate from a legitimate domain, standard advice to check the sender address is no longer sufficient. Users must rely on strict operational security regarding their seed phrases. 1. Do not click any links in the "STM32 Entropy Vulnerability" email or attempt to download firmware from email prompts. 2. Never enter your recovery phrase into any website, app, or digital form; legitimate updates via the official Trezor Suite application will never require your seed phrase. 3. If you have already entered your recovery phrase on a malicious site, immediately move your funds to a new wallet with a newly generated seed phrase. ### The Supply Chain is the New Attack Vector The hardware wallet industry has spent years fortifying physical devices against tampering, but this coordinated phishing campaign proves that attackers have simply pivoted to the weakest link: third-party marketing and logistics vendors. When a phishing email passes every standard authentication check because it originates from a legitimate domain, the traditional advice of verifying the sender address becomes dangerously obsolete. The compounding effect of the ShipMonk data leak - which provided attackers with the exact names and addresses of 80,000 Trezor customers - means these emails can be highly personalized, dramatically increasing their success rate. Hardware wallet manufacturers must now apply the same zero-trust security models they use for their firmware to their entire operational supply chain, or risk losing user trust entirely. ## Sources - [financefeeds.com](https://financefeeds.com/trezor-phishing-email-provider-breach-stm32/)