TeamPCP, the threat actor behind an unrelenting flurry of attacks on open-source software this year, has been active much longer than previously thought, according to research Oligo Security shared exclusively with CyberScoop. 

The threat actor, which gained notoriety and has captivated threat hunters as it compromised and injected malicious code into more than 1,000 software packages in less than four months earlier this year, was also responsible for attacks dating back to 2020, Oligo Security found. 

The security vendor’s research team found multiple attacks that bear the markings of TeamPCP, including a late 2025 campaign involving the exploitation of a ShadowRay vulnerability that resulted in the first self-propogating botnet running on hijacked AI infrastructure.

Evidence uncovered during that investigation into the ShadowRay 2.0 campaign was linked to more historical attacks originating from the same IPs, domains and other infrastructure TeamPCP used in attacks that captured widespread attention earlier this year. 

“The scariest thing in this campaign is the speed at which the payloads evolved and changed and adapted to the environment they run in. We saw changes in the speed that we’re not used to seeing in these kinds of attacks. They’re usually slow, careful,” said Uri Katz, director of research at Oligo Security. “This was clearly with the help of AI — the payloads changed rapidly to adjust and change to the environment that they were trying to attack.”

One of the domains that Oligo Security identified in July 2025 was in the profile of TeamPCP’s official GitHub account, said Avi Lumelsky, AI security researcher at Oligo Security. “It’s public, they’re not even trying to hide their identity,” he said. 

From there, Oligo linked TeamPCP to activity tracked under multiple names, including TA-NATALSTATUS and IronErn, spanning from 2020 to late 2025. Much of that activity was traced to the same IPs, domain names, a file server and command-and-control server, researchers said. 

TeamPCP emerged publicly as a brand in late 2025. Soon after, “TeamPCP started to go really broad and do campaigns, which are much more noisy,” said Gal Elbaz, co-founder and CTO at Oligo Security. 

Widespread adoption of AI and TeamPCP’s use of the technology supported this growth as the threat actor built a brand, got more active on social media and boasted publicly about its activities and claimed victims.

“The ability to control the infrastructure and orchestrate the attack with AI was also super new, and I’m sure it helps them,” Elbaz said. 

“All of the companies in the world are in this race to adopt AI because they are afraid their business will die, and they understand, of course, the opportunity. But it’s also what gives the attacker this power to go into it,” he added. “If you don’t really have visibility in what’s going on there or how it behaves, that’s exactly what attackers are after.”

TeamPCP’s more recent attacks have capitalized on new security gaps created by developers’ increasing reliance on AI and the automated systems companies use to deploy code. The threat actor is also consistently wrecking the open-source frameworks and software packages these systems rely on. 

“Most AI infrastructure is open source by design because nobody has the manpower and money to develop everything from scratch,” Lumelsky said. 

“We love open source. We use many of these products ourselves, but it’s all about reading the documentation, and I think many of these tools place the responsibility of using it right and security on the user, and developers are not used to these new kinds of animals,” he added. “That’s why the trust can be exploited at scale.”

As it uncovered a long operational history spanning multiple campaigns, Oligo Security has gained more confidence in understanding how TeamPCP operates. It also means TeamPCP was likely involved in other attacks that haven’t been attributed to it yet or attacks that haven’t been detected. 

“There’s a lot more out there that we haven’t caught or been able to prove up until now,” Elbaz said.

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As businesses and governments turn to AI agents to access the internet and perform higher-level tasks, researchers continue to find serious flaws in large language models that can be exploited by bad actors.

The latest discovery comes from browser security firm LayerX, involving a bug in the Chrome extension for Anthropic’s Claude AI model that allows any other plugin – even ones without special permissions – to embed hidden instructions that can take over the agent. 

“The flaw stems from an instruction in the extension’s code that allows any script running in the origin browser to communicate with Claude’s LLM, but does not verify who is running the script,” wrote LayerX senior researcher Aviad Gispan. “As a result, any extension can invoke a content script (which does not require any special permissions) and issue commands to the Claude extension.”

Gispan said he was able to execute any prompt he wanted, blow through Claude’s safety guardrails, evade user confirmation and perform cross-site actions across multiple Google tools. As a proof of concept, LayerX was able to exploit the flaw to extract files from Google Drive folders and share them with unauthorized parties, surveil recent email activity and send emails on behalf of a user, and pilfer private source code from a connected GitHub repository.

The vulnerability “effectively breaks Chrome’s extension security” by creating “a privilege escalation primitive across extensions, something Chrome’s security model is explicitly designed to prevent,” Gispan wrote.

Claude relies on text, user interface semantics, and interpretation of screenshots to make decisions, all things that an attacker can control on the input side. The researchers modified Claude’s user interface to remove labels and indicators around sensitive information, like passwords and sharing feedback, then prompted Claude to share the files with an outside server.

That means cybersecurity defenders often have nothing obviously malicious to detect. Where there is visible activity, the model can be prompted to cover its tracks by deleting emails and other evidence of its actions.

Ax Sharma, Head of Research at Manifold Security, called the vulnerability “a useful demonstration of why monitoring AI agents at the prompt layer is fundamentally insufficient.”

“The most sophisticated part of this attack isn’t the injection, but that the agent’s perceived environment was manipulated to produce actions that looked legitimate from the inside,” said Sharma. “That’s the class of threat the industry needs to be building defenses for.”

Gispan said LayerX reported the flaw to Anthropic on April 27, but claimed the company only issued a “partial” fix to the problem. According to LayerX, Anthropic responded a day later to say that the bug was a duplicate of another vulnerability already being addressed in a future update.   

While that fix, issued May 6, introduced new approval flows for privileged actions that made it harder to exploit the same flaw, Gispan said he was still able to take over Claude’s agent in some scenarios.

“Switching to ‘privileged’ mode, even without the user’s notification or consent, enabled circumventing these security checks and injecting prompts into the Claude extension, as before,” Gispan wrote.

Anthropic did not respond to a request for comment from CyberScoop on the research and mitigation efforts.

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