US Government Order Forces Anthropic to Suspend Fable 5 and Mythos 5 Models Over Jailbreak Fears
English summary
On June 12, 2026, Anthropic received a US government export control directive ordering the suspension of all access to its Fable 5 and Mythos 5 models for foreign nationals, forcing the company to disable both models for all customers. The directive cites a jailbreak method that can identify minor software vulnerabilities in a specific codebase, but Anthropic states that similar capabilities exist in other public models like OpenAI's GPT-5.5 and are routinely used by defenders. Access to all other Anthropic models remains unaffected. The blogger independently verified that Fable 5 was still accessible until 6:59pm Pacific Time, after which API calls returned a 404 error.
Chinese summary
2026年6月12日，Anthropic收到美国政府出口管制指令，要求暂停所有外国公民对Fable 5和Mythos 5模型的访问，公司被迫向所有客户禁用这两个模型。指令称存在一种越狱方法，可在特定代码库中识别微小软件漏洞，但Anthropic表示类似的越狱能力在OpenAI的GPT-5.5等其他公开模型中同样存在，且常被防御者使用。其他Anthropic模型访问不受影响。博主实测确认Fable 5在太平洋时间18:59前仍可访问，此后API返回404错误。
Key points
Anthropic received a US export control directive on June 12, 2026 at 5:21pm ET, ordering suspension of all Fable 5 and Mythos 5 access for foreign nationals.
Anthropic于2026年6月12日美东时间17:21收到美国出口管制指令，要求暂停所有外国公民对Fable 5和Mythos 5的访问。
The directive was issued due to a reported jailbreak that could find minor software vulnerabilities, but Anthropic says this capability is not unique and is present in other models like GPT-5.5.
指令源于一种可发现微小软件漏洞的越狱方法，但Anthropic表示该能力并非独有，GPT-5.5等其他模型也具备。
Fable 5 and Mythos 5 were disabled for all customers to ensure compliance; access to other Anthropic models is unchanged.
为确保合规，Fable 5和Mythos 5已对所有客户禁用；其他Anthropic模型访问不受影响。
The blogger tracked the shutdown: Fable 5 became unavailable at 6:59pm Pacific on June 12, returning a 404 error.
博主追踪了关闭过程：Fable 5于太平洋时间6月12日18:59起不可用，API返回404错误。