A security researcher found a flaw in Anthropic's Claude Code GitHub Action that let an attacker take over vulnerable public repositories running it, with nothing more than a single opened GitHub issue. Because Anthropic's own action repo used the same workflow, a working attack could have pushed malicious code into the action itself and onto the projects downstream that pull it.
RyotaK of GMO
Over the past several weeks, the cybersecurity community has been reminded how quickly frontier and agentic AI in defense networks can challenge our assumptions. When Anthropic's Claude Mythos model was made available to a limited set of organizations as a technical preview, it was reported that an unauthorized group claimed that it had gained access within hours. The incident, if true, was
It got stupid again.
The internet still feels held together with tape. Bad plugins, old bugs, fake tools, trusted apps doing shady things. Same mess, new wrapper. And now the weird stuff is normal. Forums go down and come back worse. Cheap hackers get better toys. AI starts breaking real systems. Great.
Read the whole thing before it ruins your week anyway.
Unauthenticated
WebAssembly is traditionally thought of as a mechanism to run compiled code inside your browser, but rarely as a mechanism to run full application code directly on host. We hacked up the Wazero implementation of WebAssembly and modified it to transform existing GoLang security tooling into analyst resistant malware. This isn't just a toy implementation either, we've implemented every major host API such that we can compile a full Sliver binary to run on MacOS or Windows.
This blog post covers the implementation details behind our Go->WASM compilation process and sets up our final blog post (coming next week) where we'll discuss a similar C#->WASM compilation pipeline. The tooling described in this blog post will be open sourced next week. Will be happy to answer any questions about this in the comments!
A new China-linked cybercrime group known as TA4922 has expanded its targeting focus to target European organizations in the U.K., Germany, Italy, and South Africa.
These efforts have been complemented by a "rapid operational tempo" and a continually evolving malware arsenal comprising known families like ValleyRAT (aka Winos 4.0) and Atlas RAT (aka AtlasCross RAT), as well as previously
MI5 and its international allies are once again warning that China is shopping for state secret leakers on popular recruitment platforms, including LinkedIn, Indeed, and Upwork. In a fresh advisory published on Wednesday evening, the UKโs domestic counter-intelligence agency said China is using an increasing number of platforms to recruit those who have access to classified or privileged information. Chinese military intelligence officers specifically target security clearance holders, including marks working in defense, security, and foreign affairs, military personnel, and those with indirect access to government information, such as academics, journalists, think tank employees, and others. Anyone who fits the bill is being urged to remain vigilant to potential attempts from Chinese operatives to cultivate long-term relationships. โThese actors use an aggressive online recruitment strategy whereby intelligence officers or their affiliates pose as employees of private consultancies, think tanks, or human resources firms, and place online job advertisements for foreign policy and defence analysts (or similar),โ the advisory [PDF] states. โSuccessful candidates are pressured to provide 'non-public' information for unspecified clients who are associated with the Chinese government. Chinaโs military intelligence services ultimately seek to acquire privileged military, political, and economic intelligence that can provide China with a strategic and tactical advantage over the Five Eyes.โ According to MI5, after the job and gig-work ads are posted online, Chinaโs spies will rank the resumes they receive based on how likely a given individual is to have information of interest before interviewing them. It warned that even by sending a resume over, which includes personal details, a person is risking their own security and privacy. Targets face probing questions about who they know in government. For those in the military, they might be asked about where they were based, and what tasks they were responsible for. After demanding potential recruits complete a trial report on matters related to China, the spies will often shift conversations to encrypted messaging platforms where recruits are offered payments in exchange for increasingly privileged information. Payments may arrive through a number of online platforms, including reputable services like PayPal, Zelle, and Wise, to others more commonly associated with associated with illegality, such as Western Union and cryptocurrency. MI5 closed out its advisory with a warning to anyone even considering a life of peddling secrets to China: doing so comes with severe consequences. โCertain types of data can place the lives of frontline military or other personnel at risk, can weaken our economic prosperity, and enable interference in our democratic processes,โ it said. โIndividuals engaged in the unauthorized disclosure of sensitive or classified information could face a number of consequences, including prosecution under national laws such as those relating to espionage.โ A common theme This weekโs admonition is far from the first issued by the UK in response to this particular aspect of Chinese spiesโ tradecraft. The most recent came in November when UK security minister Dan Jarvis reminded the UK's House of Commons that members should have received information about Chinese attempts to recruit parliamentarians through identical means. In those information packs disseminated by MI5, Brit politicos were given the names of two online profiles that the counter-intelligence agency suspected of being involved in recruitment campaigns. MI5 dished out an earlier warning in 2021, saying that around 10,000 Britons had been targeted by Chinese spies over the previous five years using work platforms, posing as headhunters. The 10,000 figure, it added, was thought to be a conservative estimate, with the agency's head, Ken McCallum, saying workplace platforms were being exploited โon an industrial scale.โ The US said it was seeing similar tactics used when President Trump took office for the second time, which shortly after led to mass redundancies across federal agencies. Experts at the Foundation for Defense of Democracies (FDD) named five supposed consulting companies targeting the recently jobless via LinkedIn, Craigslist, and others, all in search of state secrets. The companies would present the fired workers with job opportunities, and as FDD senior analyst Max Lesser told The Register at the time, the layoffs, which began in February 2025, would have likely raised the risk level associated with state secrets being spilled. ยฎ
Cybersecurity researchers have shed light on a macOS malvertising campaign codenamed Operation FlutterBridge that spreads a new backdoor called FlutterShell.
According to Palo Alto Networks Unit 42, the campaign is said to be the next stage of a previously reported activity cluster dubbed JSCoreRunner (aka FileRipple) in late August 2025. The cybercrime group behind the two attack chains is
Two former RAC workers in the UK have three months to pay more than ยฃ118,000 ($158,500) collectively after being convicted of selling crash victimsโ data, according to the Information Commissionerโs Office (ICO). Debbie Okparavero and Maliha Islam, of Salford and Manchester respectively, were sentenced to six-month prison stints, suspended for 18 months, and 150 hoursโ unpaid work in 2024, after being found guilty of offenses under the Computer Misuse Act 1990 and the Data Protection Act 2018. The pair, who worked for roadside accident biz RAC, were caught selling the personal data of car crash victims โ just shy of 30,000 lines of data to an unknown buyer, the ICO revealed following an investigation. Okparavero and Islam were in a WhatsApp chat together, where they discussed the data and its sale to the unknown third party. RAC clocked on to the activity after deploying unspecified monitoring software, which detected Okparavero copying the data from RAC systems. A resulting investigation showed that around 29,500 lines of data were shared with Islam via WhatsApp. Islam was ordered to repay ยฃ39,522.50 ($48,274.45) for her part in the scheme in November, and the ICO noted in a Thursday announcement that she paid this in full. Reflecting more serious offending, at Manchester Crown Court on May 29, Okparavero was ordered to repay ยฃ89,277.32 ($119,962.38) within three months. Failure to do so will result in her serving 18 months in prison. Andy Curry, head of investigations at the ICO, said: โThis outcome demonstrates justice did not end at sentencing. Our powers enabled us to continue to pursue these two individuals in order to strip them of assets gained through their serious criminal activity. Through the Proceeds of Crime Act, we are ensuring people do not financially benefit from their criminal activity. โI would like to once again thank the RAC for informing us about this breach and fully supporting the ICOโs investigation, which enabled us to hold these two individuals to account.โ ยฎ
Cybersecurity researchers have flagged a large-scale operation that impersonates open-source and freeware projects to funnel unsuspecting users through a Traffic Distribution System (TDS) and deliver malware families like Remus Stealer, AnimateClipper, and the SessionGate framework.
"The sites are well-designed and often look like legitimate project portals at a glance, sometimes referencing