Jon Tetreault

Writing

Plain-language pieces on a complicated space.

Selected writing and channels. The through-line: who really owns this thing, and how do you keep it?

Essay · Oct 2026

The Fix Was Already Out

Core Lightning told operators on October 2 that attackers are targeting nodes on version 26.06.7 or earlier. The fix had been public since September 22, with a plain-English changelog. Why a Lightning node is a hot wallet, what a revoked commitment costs, and six things to do with your node today.

Essay · Oct 2026

The Module Was the Signer

Two Safe multisigs lost 114 ETH on October 1 with no stolen key and no forged signature. A leverage module checked permission by asking the caller, and a fake Safe said yes. Why a module is a signer with a threshold of one, and what to do with every Safe you sign for.

Essay · Sep 2026

The Approval Was Real

By Bitget's account, $387.5 million left the exchange without a stolen key or a forged customer request: a compromised backend fed spoofed data to its own approval process. What a signature really proves, what an exchange balance really is, and what to do as withdrawals reopen.

Essay · Sep 2026

The Interview Was the Install

Seven agencies in four countries say North Korean fake recruiters compromised at least 30,000 PCs and over 7,000 crypto wallets through job interviews and coding tests. Why the VS Code trust prompt is the real boundary, and why your keys don't belong on the machine where you open other people's code.

Essay · Sep 2026

A Patch Can't Take Back a Key

11.7 million XRP left D'CENT App Wallet users over six days, most of it after the warning, and the attacker came back to reuse keys on emptied accounts. Why an update can't un-leak a recovery phrase, and what to do when yours may be exposed.

Essay · Sep 2026

The Name Became the Command

Since Bitcoin Core 24.0, a crafted wallet name could run commands on nodes using -walletnotify. The fix is in the 32.0 release candidate and none of the stable lines. Who is exposed, and the check to run on your own node today.

Essay · Sep 2026

The Request Came From the Right Address

Revolut handed passports, home addresses and bitcoin histories to fake requests sent from a real government email domain. Why that list is what physical attackers shop for — and the call-back habit that stops the phishing that follows.

Essay · Sep 2026

Reading Leaves No Trace

Malware is now storing its command-and-control addresses in smart contracts on BNB Chain and Polygon. The ledger keeps the address book and no record of who opened it — plus the one rule that stops the attack cold.

Essay · Sep 2026

Every Signature Was Legitimate

About $320M in bitcoin left the Liquid sidechain with every key intact. Why eleven-of-fifteen is no protection when all fifteen run the same wrong code — and why a chain that hides its amounts can't be audited for its own supply.

Essay · Sep 2026

Nobody Sent the Warning

A critical bug was reported in April, cleared as low-risk, and silently patched in August. Then it emptied six chains. What the Cosmos EVM exploit teaches about upstream trust.

Essay · Aug 2026

The Safest Place in Crypto Just Got Robbed

On the $116M Coldcard exploit: why the device was never the security, what the SafePal breach means for wallet owners, and the habits that actually protect cold storage.

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Essays from the earliest years are archived on Medium.