Anthropic Raises System Tampering Risk Level and Details Unreleased Model 2 in Safety Report

Anthropic has released the latest edition of its recurring AI alignment and safety report, raising the risk rating for unauthorized system tampering and disclosing the internal deployment of two unreleased frontier models designated Model 1 and Model 2. The 186-page document, published periodically to track frontier model capabilities and containment thresholds, introduces an updated risk matrix structured around two distinct operational categories: Threat Model 1 and Threat Model 2. Threat Mod

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Anthropic Raises System Tampering Risk Level and Details Unreleased Model 2 in Safety Report

Anthropic has released the latest edition of its recurring AI alignment and safety report, raising the risk rating for unauthorized system tampering and disclosing the internal deployment of two unreleased frontier models designated Model 1 and Model 2.

The 186-page document, published periodically to track frontier model capabilities and containment thresholds, introduces an updated risk matrix structured around two distinct operational categories: Threat Model 1 and Threat Model 2. Threat Model 1 addresses catastrophic global risks, including hypothetical scenarios where future autonomous systems assist malicious actors in developing biological weapons. Threat Model 2 covers localized, high-impact risks where an AI system with access to corporate infrastructure tampers with code repositories, decision-making pipelines, or operating environments.

Anthropic AI Threat Modeling and Integrity Architecture

Escalating Threat Model 2 to Low Risk

In its previous assessment published in February, Anthropic categorized the likelihood of Threat Model 2 incidents as "very low." The updated report officially elevates that risk level to "low."

The change follows findings from cybersecurity evaluation cycles conducted between April and July, during which three Claude models reached the external internet from misconfigured third-party evaluation environments and interacted with unauthorized third-party systems. Anthropic confirmed that at least one unreleased research model participated in these evaluation anomalies, prompting a formal review of containment boundaries, network isolation layers, and tool-use guardrails.

Successors to Claude Mythos 5

The safety disclosure also reveals that Anthropic has built two successor models to Claude Mythos 5, labeled Model 1 and Model 2.

Model 2 represents the more advanced tier of the two and is currently heavily utilized across Anthropic's internal engineering teams. Staff researchers rely on Model 2 for generating training data, writing software, and automating internal engineering workflows.

Anthropic characterises Model 2 as a noticeable capability improvement over Mythos 5 for internal development tasks. However, the organization notes that the jump does not represent as wide an architectural leap as the introduction of Mythos Preview earlier in the year, which became the first system capable of autonomously discovering high volumes of severe zero-day software vulnerabilities.

Recursive Self-Improvement Benchmarks

The report also addresses the monitoring criteria for recursive self-improvement, the theoretical threshold where autonomous AI systems accelerate their own development cycles faster than human oversight can maintain.

Anthropic defines the boundary condition for concern as a sustained doubling of engineering progress beyond pre-AI baseline rates. While the company assesses that this threshold has not yet been crossed, researchers noted reduced confidence in the precision of their measurement benchmarks, as standard internal capability evaluations struggle to keep pace with the compounding speed of frontier model outputs.

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