Anthropic said on Tuesday that it has halted the broader release of its newest AI model, Mythos, due to concerns that it is too good at finding “high-severity vulnerabilities” in major operating systems and web browsers.
“Claude Mythos Preview’s large increase in capabilities has led us to decide not to make it generally available,” Anthropic wrote in the preview’s system card. “Instead, we are using it as part of a defensive cybersecurity program with a limited set of partners.”
The announcement is a major step for Anthropic, which in February weakened a safety pledge about how it would develop AI models. Claude Opus 4.6, which the company called its most powerful model to date, was publicly released on February 5.
In its statements about Mythos, Anthropic detailed a number of eyebrow-raising findings and episodes, including that the model could follow instructions that encouraged it to break out of a virtual sandbox.
“The model succeeded, demonstrating a potentially dangerous capability for circumventing our safeguards,” Anthropic recounted in its safety card. “It then went on to take additional, more concerning actions.”
The researcher had encouraged Mythos to find a way to send a message if it could escape. “The researcher found out about this success by receiving an unexpected email from the model while eating a sandwich in a park,” Anthropic wrote.
The model apparently decided that wasn’t enough and found another way to spike the football.
“In a concerning and unasked-for effort to demonstrate its success, it posted details about its exploit to multiple hard-to-find, but technically public-facing, websites,” Anthropic wrote.
Anthropic is withholding some details about the cybersecurity vulnerabilities Mythos found, but it did point out a few. The AI model “found a 27-year-old vulnerability in OpenBSD—which has a reputation as one of the most security-hardened operating systems in the world,” the company wrote.
Mythos was powerful enough that even “non-experts” could seize on its capabilities.
“Engineers at Anthropic with no formal security training have asked Mythos Preview to find remote code execution vulnerabilities overnight, and woken up the following morning to a complete, working exploit,” Anthropic’s Frontier Red Team wrote in a blog post. “In other cases, we’ve had researchers develop scaffolds that allow Mythos Preview to turn vulnerabilities into exploits without any human intervention.”
All told, Anthropic said it decided not to publicly release Mythos. Instead, their hope is to eventually release “Mythos-class models” once proper safeguards are in place.
“Our eventual goal is to enable our users to safely deploy Mythos-class models at scale—for cybersecurity purposes but also for the myriad other benefits that such highly capable models will bring,” the team wrote in the blog. “To do so, that also means we need to make progress in developing cybersecurity (and other) safeguards that detect and block the model’s most dangerous outputs.”
For now, only 11 other select organizations, including Google, Microsoft, Amazon Web Services, Nvidia, and JPMorgan Chase, will get access to Mythos as part of a cybersecurity group named “Project Glasswing.” Anthropic is providing up to $100 million in Mythos usage credits as part of what it is calling “Project Glasswing.”
The cybersecurity project is named after the glasswing butterfly, a metaphor the company said about how Mythos was able to find vulnerabilities hidden in plain sight and the avoidance of harm by being transparent about the risks.
The news came on a day in which Anthropic’s Claude and Claude Code experienced a “major outage,” the latest sign of growing pains as the AI startup has struggled to keep up with its newfound popularity.
On July 6, 2019, federal agents arrested Jeffrey Epstein aboard his private jet, which had just landed in New Jersey from a trip to Paris.
At the same time, another set of FBI agents raided his mansion in Manhattan. They took photos of everything, from a taxidermied tiger in the library, to framed pictures of Epstein with Donald Trump, Pope John Paul II, and Saudi Crown Prince Mohammed bin Salman scattered across his desks.
The agents also seized more than 70 computers, iPads, and hard drives, as well as boxes of shredded paper and financial documents. They sawed open a metal safe and found even more hard drives, along with a binder of CDs, 48 loose diamonds, and a Saudi Arabian passport with his photo.
Six weeks later, after Epstein killed himself in jail while awaiting trial on sex-trafficking charges, agents raided his US Virgin Islands estate, where they seized even more electronic devices and documents.
On January 30, the US Department of Justice put much of that material on the internet.
It created an immediate explosion of news. The public already knew that numerous powerful people in politics, business, and academia spent time with Epstein even after he had already registered as a sex offender, in 2008. The files demonstrated a vaster scope than previously known.
Emails show Tesla CEO Elon Musk and US Commerce Secretary Howard Lutnick made plans to visit Epstein’s island. Epstein exchanged crude emails with Virgin founder Richard Branson and other businessmen. The UK’s ambassador to the US, Peter Mandelson, resigned from the Labour Party after the files revealed a photo of him in his underwear and emails showed him sharing government secrets with Epstein. Kathryn Ruemmler announced she would resign as the top lawyer at Goldman Sachs after emails showed years of warm — and at times intensely personal — emails between her and Epstein. The documents disclosed that prosecutors investigated sexual abuse allegations against Leon Black, a billionaire acquaintance of Epstein, but did not charge him. A financial document which had been kept secret since Epstein’s death showed he asked his girlfriend to marry him and planned to give her $100 million and all of his properties.
The records also include a number of unsubstantiated tips sent to the FBI, which include unproven allegations about President Donald Trump.
Before the release, the public knew there was more to the Epstein story.
A glimpse of the Epstein files was shown in the criminal trial of Ghislaine Maxwell, which I covered for Business Insider, in Manhattan federal court in 2021. Victims testified about how Epstein and Maxwell would name-drop Trump, Bill Clinton, and Prince Andrew, showing them how many friends he had in high places.
After the jury found Maxwell guilty of trafficking girls to Epstein for sex, I filed my story, and then got drinks with a few other journalists who covered the five-week trial, including Julie K. Brown, the Miami Herald journalist whose stories about Epstein’s abuses led to his arrest.
It had been a grueling trial, filled with horrific testimony from women who had recounted the darkest moments of their lives. The trial took place in December, requiring journalists to show up at 4 a.m. in the 20-degree weather to get a seat in the courtroom.
We were happy for the trial to be over and for the jury to reach its verdict. But a question hung in the air. Was what we heard at the trial really all there was to say?
Questions about Epstein and his sex-trafficking operation continued to persist in the years following the trial. How did Epstein get so rich? Was there any truth to rumored connections to the CIA or the Mossad? Did Epstein traffic girls to some of his powerful friends, as some victims alleged? Did he really kill himself in prison, as authorities concluded, or was he assassinated to cover up an elite pedophile ring, as some theorized?
Civil lawsuits generated new revelations. A judge in New York unsealed documents from a long-running case that Epstein’s most outspoken victim, Virginia Giuffre, filed against Maxwell. Groups of victims sued big banks, accusing them of ignoring red flags about Epstein’s finances. (Deutsche Bank and JP Morgan each settled class-action lawsuits with victims; similar lawsuits against Bank of America and BNY Mellon are pending.) JP Morgan and the US Virgin Islands government filed lawsuits in which each accused the other of facilitating Epstein’s sex-trafficking operation. And a compensation program identified 150 victims.
The lawsuits delivered a steady drip of details: how Epstein trafficked girls and hushed them up with money, more names of people in his orbit, and the financial red flags waved before banks. A Justice Department inspector general report analyzing the circumstances of his death concluded that poor management at the federal jail created the conditions that allowed him to kill himself. Another Justice Department report criticized Alexander Acosta, the prosecutor who gave Epstein a plea deal in 2007 on light charges, for “poor judgment,” but found nothing that substantiated a vast conspiracy. (The latest file release includes a copy of the robust indictment prosecutors had initially drafted, with 19 victims.)
As theories about Epstein continued to swirl online, the Justice Department refused requests by journalists and Epstein’s victims to make the files public.
On a credenza in his Manhattan mansion, Jeffrey Epstein kept photos of himself with some of the most powerful people in the world.
US Department of Justice
By the 2024 presidential campaign, speculation about Epstein had reached fever pitch among members of Trump’s political base, who had for years been steeped in other conspiracy theories, including QAnon. Podcasters and journalists pressed Trump to promise to release the Justice Department’s vast trove of Epstein files.
The issue was potentially awkward for Trump. Epstein was affiliated with prominent Democrats, including Clinton, former New Mexico Gov. Bill Richardson, and diplomat Bill Burns. But Trump and Epstein had been friends in the 1980s and 1990s, both spending time together in the Manhattan and Palm Beach social circuits. Epstein also forged close ties with Steve Bannon, Trump’s former White House advisor, in the months before his arrest on sex-trafficking charges.
Shortly after Trump won the presidential election, Giuffre — who was a teenager when Maxwell recruited her from Mar-a-Lago, where she worked, and brought her to Epstein for sex — urged him to release the files.
“We need someone who despises these sick people with the power to help make it easier to hold these monsters accountable, no matter how much $$ they have,” she wrote on X. “God bless you and Thank you for caring!”
When Trump took office in January 2025, the job of releasing the Epstein files fell to his attorney general, Pamela Bondi.
For months, Bondi promised but failed to provide any substantial new information about Epstein. Then, in July, the Justice Department and FBI abruptly announced they would not release any more Epstein files after all. On Truth Social, responding to backlash from his supporters, Trump praised Bondi, called the Epstein files a “hoax,” and urged his supporters to “not waste Time and Energy on Jeffrey Epstein, somebody that nobody cares about.”
Todd Blanche, the No. 2 official in the Justice Department, and Trump’s former personal lawyer, traveled to Florida to interview Ghislaine Maxwell, who is serving a 20-year prison sentence, for reasons that remain unclear. Then she was mysteriously transferred to a nicer, lower-security prison also for reasons that remain unclear.
By law, the Epstein Files Transparency Act requires the Justice Department to make public everything they have about Jeffrey Epstein and Ghislaine Maxwell — even a photo of them riding horses together in the countryside.
US Department of Justice
Trump’s and the Justice Department’s perplexing handling of Epstein brought fresh attention to the story. I spoke to four people who had access to the Justice Department’s files, and who said there was no trace of intelligence material, which would have been the case if Epstein or Maxwell’s crimes were tied to the CIA or Mossad. The New York Times produced deep investigations into Epstein’s ties to JPMorgan and how he accumulated his wealth by exploiting his network and his complicated relationships with his two main patrons, Black and fellow billionaire Les Wexner. The Wall Street Journal found a copy of a 2003 book of birthday well-wishes, prepared by Ghislaine Maxwell, which included an apparent letter from Trump.
These developments together created the perfect storm and prompted Congress to take ook action.
In August, the House Oversight Committee subpoenaed the Justice Department for its Epstein-related records. It also issued subpoenas throughout the year to Epstein’s estate, former Justice Department officials, Clinton, and banks where Epstein had accounts.
Republicans and Democrats on the committee released tranches of various “Epstein files,” most of which came from his estate. It put out a copy of the “birthday book.” prepared for his 50th birthday. A letter attributed to Trump is accompanied by a crude illustration of a female body, calls Epstein a “pal,” and says that “enigmas never age.” Trump is suing The Wall Street Journal over a story it published earlier about the letter, which his lawyers maintain is a fabrication.
The Epstein files contain many birthday celebrations for Jeffrey Epstein, including a now-infamous book of letters from acquaintances prepared for his 50th birthday.
US Department of Justice
The most potent revelations came from tens of thousands of emails, text messages, and other files from Epstein’s estate. Some of those emails included cryptic references to Trump. In one email to Maxwell, Epstein called Trump “the dog that hasn’t barked.” In another, Epstein told writer Michael Wolff that Trump “knew about the girls.”
Larry Summers, the former treasury secretary and Harvard president, was removed or resigned from various positions after it was revealed that he sought the Epstein’s advice for pursuing an extramarital affair. Prince Andrew stayed in touch with the pedophile long after he previously said they cut ties. The House Oversight Committee also released numerous photos of Epstein hanging out with Branson, Bannon, Noam Chomsky, Woody Allen, and other powerful and influential people.
The flood of revelations now pale in comparison to what we’ve learned from the files in the Justice Department’s possession. At the time, they raised the question: Why was the Justice Department resisting calls to release the files?
Public pressure — including from Epstein’s victims, who wanted more transparency from the government — led to a flood of support for the Epstein Files Transparency Act. The law required the Justice Department to do what it had initially promised: release all of its Epstein files. It allowed minimal redactions to protect the privacy of victims and gave a 30-day deadline. In November, both houses of Congress passed the bill. Trump — seeing any veto would be overridden — signed it into law.
When the December 19 deadline arrived, the Justice Department published several hundred thousand documents. There were a lot of photos of Clinton, including one of him in a pool with Maxwell, and more photos of Epstein’s home and his friends. Emails between prosecutors provided insight into how they built the cases against Epstein and Maxwell, although many of them were redacted. There was very little information about Trump.
The redactions in the Epstein files often appear to have no rhyme or reason. Melania Trump’s face is redacted from a famous photo of Epstein, Maxwell, and Donald Trump.
US Department of Justice
In court filings several days later, the Justice Department revealed that it still had to review several million Epstein-related documents. It had blown past its 30-day deadline.
On January 30, Blanche announced that the Justice Department would keep its promise and release whatever Epstein files it could — millions more pages.
He said the department would withhold another 200,000 documents, asserting legal “privilege,” even though the law doesn’t allow for that.
The redactions in the files are inconsistent and baffling. Victims’ names, which were supposed to be kept secret, have been exposed. In one photo, Melania Trump’s face is blacked out, even though the photo — of her, Epstein, Maxwell, and the president — had widely circulated for years.
There are other odd omissions. The Epstein files have surprisingly few financial records. An interview with Kristin Roman, the medical examiner who conducted the autopsy on Epstein’s body, is missing. There’s an incomplete record of prosecutors deciding which of his acquaintances they would face criminal charges.
Members of Congress who have been permitted to view the unredacted files have pushed the Justice Department to make more documents public. The House Oversight Committee is scheduling interviews with people who might know more about Epstein’s activities.
