At least 187 code packages made available through the JavaScript repository NPM have been infected with a self-replicating worm that steals credentials from developers and publishes those secrets on GitHub, experts warn. The malware, which briefly infected multiple code packages from the security vendor CrowdStrike, steals and publishes even more credentials every time an infected package is installed.

Image: https://en.wikipedia.org/wiki/Sandworm_(Dune)

The novel malware strain is being dubbed Shai-Hulud — after the name for the giant sandworms in Frank Herbert’s Dune novel series — because it publishes any stolen credentials in a new public GitHub repository that includes the name “Shai-Hulud.”

“When a developer installs a compromised package, the malware will look for a npm token in the environment,” said Charlie Eriksen, a researcher for the Belgian security firm Aikido. “If it finds it, it will modify the 20 most popular packages that the npm token has access to, copying itself into the package, and publishing a new version.”

At the center of this developing maelstrom are code libraries available on NPM (short for “Node Package Manager”), which acts as a central hub for JavaScript development and provides the latest updates to widely-used JavaScript components.

The Shai-Hulud worm emerged just days after unknown attackers launched a broad phishing campaign that spoofed NPM and asked developers to “update” their multi-factor authentication login options. That attack led to malware being inserted into at least two-dozen NPM code packages, but the outbreak was quickly contained and was narrowly focused on siphoning cryptocurrency payments.

Image: aikido.dev

In late August, another compromise of an NPM developer resulted in malware being added to “nx,” an open-source code development toolkit with as many as six million weekly downloads. In the nx compromise, the attackers introduced code that scoured the user’s device for authentication tokens from programmer destinations like GitHub and NPM, as well as SSH and API keys. But instead of sending those stolen credentials to a central server controlled by the attackers, the malicious nx code created a new public repository in the victim’s GitHub account, and published the stolen data there for all the world to see and download.

Last month’s attack on nx did not self-propagate like a worm, but this Shai-Hulud malware does and bundles reconnaissance tools to assist in its spread. Namely, it uses the open-source tool TruffleHog to search for exposed credentials and access tokens on the developer’s machine. It then attempts to create new GitHub actions and publish any stolen secrets.

“Once the first person got compromised, there was no stopping it,” Aikido’s Eriksen told KrebsOnSecurity. He said the first NPM package compromised by this worm appears to have been altered on Sept. 14, around 17:58 UTC.

The security-focused code development platform socket.dev reports the Shai-Halud attack briefly compromised at least 25 NPM code packages managed by CrowdStrike. Socket.dev said the affected packages were quickly removed by the NPM registry.

In a written statement shared with KrebsOnSecurity, CrowdStrike said that after detecting several malicious packages in the public NPM registry, the company swiftly removed them and rotated its keys in public registries.

“These packages are not used in the Falcon sensor, the platform is not impacted and customers remain protected,” the statement reads, referring to the company’s widely-used endpoint threat detection service. “We are working with NPM and conducting a thorough investigation.”

A writeup on the attack from StepSecurity found that for cloud-specific operations, the malware enumerates AWS, Azure and Google Cloud Platform secrets. It also found the entire attack design assumes the victim is working in a Linux or macOS environment, and that it deliberately skips Windows systems.

StepSecurity said Shai-Hulud spreads by using stolen NPM authentication tokens, adding its code to the top 20 packages in the victim’s account.

“This creates a cascading effect where an infected package leads to compromised maintainer credentials, which in turn infects all other packages maintained by that user,” StepSecurity’s Ashish Kurmi wrote.

Eriksen said Shai-Hulud is still propagating, although its spread seems to have waned in recent hours.

“I still see package versions popping up once in a while, but no new packages have been compromised in the last ~6 hours,” Eriksen said. “But that could change now as the east coast starts working. I would think of this attack as a ‘living’ thing almost, like a virus. Because it can lay dormant for a while, and if just one person is suddenly infected by accident, they could restart the spread. Especially if there’s a super-spreader attack.”

For now, it appears that the web address the attackers were using to exfiltrate collected data was disabled due to rate limits, Eriksen said.

Nicholas Weaver is a researcher with the International Computer Science Institute, a nonprofit in Berkeley, Calif. Weaver called the Shai-Hulud worm “a supply chain attack that conducts a supply chain attack.” Weaver said NPM (and all other similar package repositories) need to immediately switch to a publication model that requires explicit human consent for every publication request using a phish-proof 2FA method.

“Anything less means attacks like this are going to continue and become far more common, but switching to a 2FA method would effectively throttle these attacks before they can spread,” Weaver said. “Allowing purely automated processes to update the published packages is now a proven recipe for disaster.”

At least 18 popular JavaScript code packages that are collectively downloaded more than two billion times each week were briefly compromised with malicious software today, after a developer involved in maintaining the projects was phished. The attack appears to have been quickly contained and was narrowly focused on stealing cryptocurrency. But experts warn that a similar attack with a slightly more nefarious payload could lead to a disruptive malware outbreak that is far more difficult to detect and restrain.

This phishing email lured a developer into logging in at a fake NPM website and supplying a one-time token for two-factor authentication. The phishers then used that developer’s NPM account to add malicious code to at least 18 popular JavaScript code packages.

Aikido is a security firm in Belgium that monitors new code updates to major open-source code repositories, scanning any code updates for suspicious and malicious code. In a blog post published today, Aikido said its systems found malicious code had been added to at least 18 widely-used code libraries available on NPM (short for) “Node Package Manager,” which acts as a central hub for JavaScript development and the latest updates to widely-used JavaScript components.

JavaScript is a powerful web-based scripting language used by countless websites to build a more interactive experience with users, such as entering data into a form. But there’s no need for each website developer to build a program from scratch for entering data into a form when they can just reuse already existing packages of code at NPM that are specifically designed for that purpose.

Unfortunately, if cybercriminals manage to phish NPM credentials from developers, they can introduce malicious code that allows attackers to fundamentally control what people see in their web browser when they visit a website that uses one of the affected code libraries.

According to Aikido, the attackers injected a piece of code that silently intercepts cryptocurrency activity in the browser, “manipulates wallet interactions, and rewrites payment destinations so that funds and approvals are redirected to attacker-controlled accounts without any obvious signs to the user.”

“This malware is essentially a browser-based interceptor that hijacks both network traffic and application APIs,” Aikido researcher Charlie Eriksen wrote. “What makes it dangerous is that it operates at multiple layers: Altering content shown on websites, tampering with API calls, and manipulating what users’ apps believe they are signing. Even if the interface looks correct, the underlying transaction can be redirected in the background.”

Aikido said it used the social network Bsky to notify the affected developer, Josh Junon, who quickly replied that he was aware of having just been phished. The phishing email that Junon fell for was part of a larger campaign that spoofed NPM and told recipients they were required to update their two-factor authentication (2FA) credentials. The phishing site mimicked NPM’s login page, and intercepted Junon’s credentials and 2FA token. Once logged in, the phishers then changed the email address on file for Junon’s NPM account, temporarily locking him out.

Aikido notified the maintainer on Bluesky, who replied at 15:15 UTC that he was aware of being compromised, and starting to clean up the compromised packages.

Junon also issued a mea culpa on HackerNews, telling the community’s coder-heavy readership, “Hi, yep I got pwned.”

“It looks and feels a bit like a targeted attack,” Junon wrote. “Sorry everyone, very embarrassing.”

Philippe Caturegli, “chief hacking officer” at the security consultancy Seralys, observed that the attackers appear to have registered their spoofed website — npmjs[.]help — just two days before sending the phishing email. The spoofed website used services from dnsexit[.]com, a “dynamic DNS” company that also offers “100% free” domain names that can instantly be pointed at any IP address controlled by the user.

Junon’s mea cupla on Hackernews today listed the affected packages.

Caturegli said it’s remarkable that the attackers in this case were not more ambitious or malicious with their code modifications.

“The crazy part is they compromised billions of websites and apps just to target a couple of cryptocurrency things,” he said. “This was a supply chain attack, and it could easily have been something much worse than crypto harvesting.”

Aikido’s Eriksen agreed, saying countless websites dodged a bullet because this incident was handled in a matter of hours. As an example of how these supply-chain attacks can escalate quickly, Eriksen pointed to another compromise of an NPM developer in late August that added malware to “nx,” an open-source code development toolkit with as many as six million weekly downloads.

In the nx compromise, the attackers introduced code that scoured the user’s device for authentication tokens from programmer destinations like GitHub and NPM, as well as SSH and API keys. But instead of sending those stolen credentials to a central server controlled by the attackers, the malicious code created a new public repository in the victim’s GitHub account, and published the stolen data there for all the world to see and download.

Eriksen said coding platforms like GitHub and NPM should be doing more to ensure that any new code commits for broadly-used packages require a higher level of attestation that confirms the code in question was in fact submitted by the person who owns the account, and not just by that person’s account.

“More popular packages should require attestation that it came through trusted provenance and not just randomly from some location on the Internet,” Eriksen said. “Where does the package get uploaded from, by GitHub in response to a new pull request into the main branch, or somewhere else? In this case, they didn’t compromise the target’s GitHub account. They didn’t touch that. They just uploaded a modified version that didn’t come where it’s expected to come from.”

Eriksen said code repository compromises can be devastating for developers, many of whom end up abandoning their projects entirely after such an incident.

“It’s unfortunate because one thing we’ve seen is people have their projects get compromised and they say, ‘You know what, I don’t have the energy for this and I’m just going to deprecate the whole package,'” Eriksen said.

Kevin Beaumont, a frequently quoted security expert who writes about security incidents at the blog doublepulsar.com, has been following this story closely today in frequent updates to his account on Mastodon. Beaumont said the incident is a reminder that much of the planet still depends on code that is ultimately maintained by an exceedingly small number of people who are mostly overburdened and under-resourced.

“For about the past 15 years every business has been developing apps by pulling in 178 interconnected libraries written by 24 people in a shed in Skegness,” Beaumont wrote on Mastodon. “For about the past 2 years orgs have been buying AI vibe coding tools, where some exec screams ‘make online shop’ into a computer and 389 libraries are added and an app is farted out. The output = if you want to own the world’s companies, just phish one guy in Skegness.”

Image: https://infosec.exchange/@GossiTheDog@cyberplace.social.

Aikido recently launched a product that aims to help development teams ensure that every code library used is checked for malware before it can be used or installed. Nicholas Weaver, a researcher with the International Computer Science Institute, a nonprofit in Berkeley, Calif., said Aikido’s new offering exists because many organizations are still one successful phishing attack away from a supply-chain nightmare.

Weaver said these types of supply-chain compromises will continue as long as people responsible for maintaining widely-used code continue to rely on phishable forms of 2FA.

“NPM should only support phish-proof authentication,” Weaver said, referring to physical security keys that are phish-proof — meaning that even if phishers manage to steal your username and password, they still can’t log in to your account without also possessing that physical key.

“All critical infrastructure needs to use phish-proof 2FA, and given the dependencies in modern software, archives such as NPM are absolutely critical infrastructure,” Weaver said. “That NPM does not require that all contributor accounts use security keys or similar 2FA methods should be considered negligence.”

Agents with the Federal Bureau of Investigation (FBI) briefed Capitol Hill staff recently on hardening the security of their mobile devices, after a contacts list stolen from the personal phone of the White House Chief of Staff Susie Wiles was reportedly used to fuel a series of text messages and phone calls impersonating her to U.S. lawmakers. But in a letter this week to the FBI, one of the Senate’s most tech-savvy lawmakers says the feds aren’t doing enough to recommend more appropriate security protections that are already built into most consumer mobile devices.

A screenshot of the first page from Sen. Wyden’s letter to FBI Director Kash Patel.

On May 29, The Wall Street Journal reported that federal authorities were investigating a clandestine effort to impersonate Ms. Wiles via text messages and in phone calls that may have used AI to spoof her voice. According to The Journal, Wiles told associates her cellphone contacts were hacked, giving the impersonator access to the private phone numbers of some of the country’s most influential people.

The execution of this phishing and impersonation campaign — whatever its goals may have been — suggested the attackers were financially motivated, and not particularly sophisticated.

“It became clear to some of the lawmakers that the requests were suspicious when the impersonator began asking questions about Trump that Wiles should have known the answers to—and in one case, when the impersonator asked for a cash transfer, some of the people said,” the Journal wrote. “In many cases, the impersonator’s grammar was broken and the messages were more formal than the way Wiles typically communicates, people who have received the messages said. The calls and text messages also didn’t come from Wiles’s phone number.”

Sophisticated or not, the impersonation campaign was soon punctuated by the murder of Minnesota House of Representatives Speaker Emerita Melissa Hortman and her husband, and the shooting of Minnesota State Senator John Hoffman and his wife. So when FBI agents offered in mid-June to brief U.S. Senate staff on mobile threats, more than 140 staffers took them up on that invitation (a remarkably high number considering that no food was offered at the event).

But according to Sen. Ron Wyden (D-Ore.), the advice the FBI provided to Senate staffers was largely limited to remedial tips, such as not clicking on suspicious links or attachments, not using public wifi networks, turning off bluetooth, keeping phone software up to date, and rebooting regularly.

“This is insufficient to protect Senate employees and other high-value targets against foreign spies using advanced cyber tools,” Wyden wrote in a letter sent today to FBI Director Kash Patel. “Well-funded foreign intelligence agencies do not have to rely on phishing messages and malicious attachments to infect unsuspecting victims with spyware. Cyber mercenary companies sell their government customers advanced ‘zero-click’ capabilities to deliver spyware that do not require any action by the victim.”

Wyden stressed that to help counter sophisticated attacks, the FBI should be encouraging lawmakers and their staff to enable anti-spyware defenses that are built into Apple’s iOS and Google’s Android phone software.

These include Apple’s Lockdown Mode, which is designed for users who are worried they may be subject to targeted attacks. Lockdown Mode restricts non-essential iOS features to reduce the device’s overall attack surface. Google Android devices carry a similar feature called Advanced Protection Mode.

Wyden also urged the FBI to update its training to recommend a number of other steps that people can take to make their mobile devices less trackable, including the use of ad blockers to guard against malicious advertisements, disabling ad tracking IDs in mobile devices, and opting out of commercial data brokers (the suspect charged in the Minnesota shootings reportedly used multiple people-search services to find the home addresses of his targets).

The senator’s letter notes that while the FBI has recommended all of the above precautions in various advisories issued over the years, the advice the agency is giving now to the nation’s leaders needs to be more comprehensive, actionable and urgent.

“In spite of the seriousness of the threat, the FBI has yet to provide effective defensive guidance,” Wyden said.

Nicholas Weaver is a researcher with the International Computer Science Institute, a nonprofit in Berkeley, Calif. Weaver said Lockdown Mode or Advanced Protection will mitigate many vulnerabilities, and should be the default setting for all members of Congress and their staff.

“Lawmakers are at exceptional risk and need to be exceptionally protected,” Weaver said. “Their computers should be locked down and well administered, etc. And the same applies to staffers.”

Weaver noted that Apple’s Lockdown Mode has a track record of blocking zero-day attacks on iOS applications; in September 2023, Citizen Lab documented how Lockdown Mode foiled a zero-click flaw capable of installing spyware on iOS devices without any interaction from the victim.

Earlier this month, Citizen Lab researchers documented a zero-click attack used to infect the iOS devices of two journalists with Paragon’s Graphite spyware. The vulnerability could be exploited merely by sending the target a booby-trapped media file delivered via iMessage. Apple also recently updated its advisory for the zero-click flaw (CVE-2025-43200), noting that it was mitigated as of iOS 18.3.1, which was released in February 2025.

Apple has not commented on whether CVE-2025-43200 could be exploited on devices with Lockdown Mode turned on. But HelpNetSecurity observed that at the same time Apple addressed CVE-2025-43200 back in February, the company fixed another vulnerability flagged by Citizen Lab researcher Bill Marczak: CVE-2025-24200, which Apple said was used in an extremely sophisticated physical attack against specific targeted individuals that allowed attackers to disable USB Restricted Mode on a locked device.

In other words, the flaw could apparently be exploited only if the attacker had physical access to the targeted vulnerable device. And as the old infosec industry adage goes, if an adversary has physical access to your device, it’s most likely not your device anymore.

I can’t speak to Google’s Advanced Protection Mode personally, because I don’t use Google or Android devices. But I have had Apple’s Lockdown Mode enabled on all of my Apple devices since it was first made available in September 2022. I can only think of a single occasion when one of my apps failed to work properly with Lockdown Mode turned on, and in that case I was able to add a temporary exception for that app in Lockdown Mode’s settings.

My main gripe with Lockdown Mode was captured in a March 2025 column by TechCrunch’s Lorenzo Francheschi-Bicchierai, who wrote about its penchant for periodically sending mystifying notifications that someone has been blocked from contacting you, even though nothing then prevents you from contacting that person directly. This has happened to me at least twice, and in both cases the person in question was already an approved contact, and said they had not attempted to reach out.

Although it would be nice if Apple’s Lockdown Mode sent fewer, less alarming and more informative alerts, the occasional baffling warning message is hardly enough to make me turn it off.