Amazon uncovers broad North Korean hacking campaign against open-source software
New findings connect the same Pyongyang-backed group to four compromises dating to 2025, revealing a larger operation than previously known.
A North Korea-linked hacker group has been tied to four open-source software compromises dating back to March 2025, Amazon researchers said Wednesday, significantly expanding the publicly known scope of Pyongyang’s efforts to use trusted code to reach large numbers of potential victims and gain access to companies’ systems.
The assessment for the first time links the same financially-motivated hacking group to compromises of four major JavaScript packages — typo-crypto, debug, chalk and axios — that developers use as building blocks for other software. The axios package alone receives more than 100 million downloads each week, and its compromise had previously been attributed to the North Korean group.
Amazon said Wednesday that it had uncovered evidence connecting the actor to the three earlier incidents, based on technical findings that included instances of reused code and similarities in how the attacks were carried out.
Amazon Threat Intelligence attributed the campaigns to the group with “medium confidence,” according a blog post authored by Amazon Integrated Security CISO CJ Moses scheduled for release Wednesday evening. The cyber intruders are tracked by researchers under several names, including Sapphire Sleet, Stardust Chollima, BlueNoroff, CageyChameleon and Alluring Pisces.
In each incident, the hackers tricked a trusted software maintainer and used the access to publish an update containing malicious code, according to Amazon. Organizations configured to automatically download the latest version of those packages may have pulled the compromised updates directly into their systems. The approach allows hackers to compromise a small number of widely used packages while potentially gaining access to thousands of downstream systems, making it more efficient than targeting organizations individually.
Open-source software — code that can be freely inspected, modified and reused — underpins operating systems, web servers, encryption tools and many of the applications businesses rely on daily all over the world. The projects often depend on volunteer maintainers to review proposed changes, fix security flaws and publish updates.
That model relies heavily on trust. Attackers can spend weeks or months posing as legitimate contributors, fixing bugs and building relationships before attempting to gain control of an established project or publishing a malicious update.
That dynamic drew widespread attention in 2024, when an account operating under the name “Jia Tan” spent years gaining the trust of other developers before attempting to insert a backdoor into XZ Utils, a widely used data-compression tool included in numerous Linux distributions. The backdoor was discovered before it could be broadly deployed.
“Quite frankly, the open-source community is looking for good citizens because these packages are often not maintained by people who are getting paid to do that as a full-time job,” Rick Anthony, senior manager for Amazon’s Inspector vulnerability management service, told reporters in Arlington, Va. on Wednesday. “They are very welcoming for anyone who is willing to contribute.”
North Korea has long treated cyber operations as both an intelligence tool and a source of revenue. Its hackers steal cryptocurrency, conduct espionage and extort victims, while operatives posing as remote IT workers obtain jobs at foreign companies and quietly funnel their salaries back to the regime. Amazon is among those companies, executives said Wednesday. U.S. officials say the proceeds help Pyongyang evade sanctions and finance its nuclear weapons and ballistic missile programs.
“For a sanctions-constrained regime, generating revenue through these operations means that the greater the efficiency, the more money they get, and the more that they can use that money to do things that got them the sanctions to begin with,” Moses told reporters. “One successful supply chain compromise can yield access to hundreds, if not more, targeted intrusions.”
The findings also illustrate how open-source attacks are becoming harder to detect.
Amazon said attackers are increasingly dividing a malicious operation among several packages that appear harmless when reviewed individually. One package may contain encrypted data, another the code needed to unlock it and a third the instructions to download and execute the final payload. The malicious behavior becomes visible only when the components are used together.
AI is also making malicious software harder to spot, the blog warned. Hackers can use it to create polished-looking code, convincing documentation and fake developer profiles, eliminating many of the obvious mistakes that once raised red flags.
Attackers can also exploit errors made by AI coding assistants. If an AI tool recommends a software package that does not exist, hackers can register the name and load it with malware, hoping a developer or automated system will download it without realizing the recommendation was wrong.
Concerns about open-source software security have increasingly drawn attention in Washington. In December, the chairman of the Senate Intelligence Committee asked the White House national cyber director to take steps to address vulnerabilities in open-source projects that help power systems used throughout U.S. military and civilian agencies.
Last August, Nextgov/FCW first reported that an employee of the Russian technology company Yandex was the sole maintainer of a widely used open-source tool embedded in at least 30 pre-built software packages available to the Defense Department.