Key Takeaways
- In the latest NPM hack, attackers inject crypto-stealing malware into core NPM libraries.
- The malware silently intercepts web and wallet activity, cleverly swapping or hijacking victims’ crypto addresses using advanced string similarity algorithms.
- Ledger CTO Charles Guillemet warns that crypto users are especially vulnerable.
Crypto’s latest security shock, the NPM hack, arrived courtesy of a single phishing email, which compromised a reputable developer’s NPM account. It has turned some of the most popular JavaScript libraries into silent crypto siphons practically overnight.
Ledger CTO Charles Guillemet immediately took to X to warn crypto users to be vigilant.
The NPM Hack: What Happened?
NPM tools are packages that are woven into the heart of the internet, downloaded billions of times every year. If you’re building a wallet app, a crypto portfolio tracker, or even just a slick front end, odds are they’re somewhere in your software stack.
And for the millions who rely on these libraries through DeFi platforms, exchanges, and even hardware wallet integrations, this breach is about as close to “everywhere” as software vulnerabilities get.
So what happened in this NPM hack? It’s a story that feels as old as time. A reputable NPM maintainer fell victim to a targeted phishing campaign.
Hackers tricked the developer into handing over two-factor authentication details via a fake NPM support email. Then, the bad actors used those credentials to push new, malicious versions of some of the ecosystem’s most widely used packages.
From the outside, everything looked normal, with the same trusted packages and expected functionality. However, under the hood, it was a different story.
These poisoned updates contain malware so sly it can read, rewrite, and reroute crypto transactions in real-time.
A Closer Look into the Hack
The code works by quietly monitoring wallet activity like browser-based requests, wallet app calls, and even direct API communications. It then swaps out crypto destination addresses with those belonging to the attacker.
As Guillemet put it in his public warning: “The malicious payload works by silently swapping crypto addresses on the fly to steal funds.”
Meanwhile, users who think they are sending tokens to a trusted friend or a reputable exchange now risk having their funds siphoned directly to a hostile wallet. No red flags, no obvious errors, and in the spirit of crypto, no second chances.
Advanced string matching algorithms even make the malicious addresses look alarmingly similar to legitimate ones, a trick designed to brush aside cursory visual checks. This update from the NPM hack has spooked traders, with experts urging caution.
Why the Ledger CTO Is Sounding the Alarm after NPM Hack?
Ledger didn’t just wade into this mess because it’s a leader in hardware wallets. Its CTO, Charles Guillemet, flagged the attack as an urgent risk for anyone conducting on-chain business.
Why so stark? Hardware wallets, designed to display and verify transaction details independently from compromised computers or browsers, offer a last line of defense.
Outside code can’t tamper with transactions shown on a Ledger, even if malicious scripts infest a PC. Verify the address, confirm the amount; it’s the ultimate crypto checkpoint.
For software wallet users, the picture is murkier. Malware injected during the NPM hack can hijack the UI, swap addresses, and even alter what the app displays. It makes it almost impossible to be certain the transaction is safe.
Until patches are out and the security teams sweep up the mess, the Ledger CTO advises refraining from transacting. This is one storm better waited out.
Why Crypto Is So Exposed?
This NPM hack is hardly the first time crypto’s digital plumbing turned out to be a vulnerability. SushiSwap’s MISO platform suffered a $3 million theft due to a supply-chain code commit in 2021.
In 2023, the infamous 3CX hack used supply chain tactics to target crypto companies across industries, with attackers leveraging trojaned installers to steal digital assets at scale.
Even government agencies have learned the hard way: supply chain attacks are as much about trust as they are about code, and in crypto, trust evaporates quickly.
Even as security teams work to purge infected packages from the NPM hack, the reality is clear: any open-source dependency is a potential Trojan horse.
Source: https://www.thecoinrepublic.com/2025/09/09/ledger-cto-warns-crypto-users-at-risk-from-billion-download-npm-hack/
