Yesterday in AI: 26 March 2026 — Leaks, Limits, and a Security Reality Check

Anthropic's next flagship model surfaces via a data leak, AI-generated code is tied to 74 CVEs, and MCP crosses 97 million monthly downloads.

By OMC Editorial on 2026-03-27

Anthropic's most powerful model slipped out of the shadows via an unsecured data store, a Georgia Tech study landed a sobering verdict on AI-generated code security, and MCP crossed 97 million monthly downloads — all in one day. Claude Mythos Surfaces in a Data Leak Anthropic's next flagship, reportedly named Claude Mythos, was exposed when a draft blog post ended up in a publicly searchable, unsecured data store. Fortune obtained the document, and an Anthropic spokesperson confirmed Mythos represents "a step change in AI performance" and is "the most capable we've built to date." The draft also flagged that the model poses "unprecedented cybersecurity risks" — strong language even for a safety-focused company. Mythos is currently in early access with select customers. The accidental disclosure raises operational-security questions at a critical competitive moment. Source: Fortunehttps://fortune.com/2026/03/26/anthropic-says-testing-mythos-powerful-new-ai-model-after-data-leak-reveals-its-existence-step-change-in-capabilities/ Anthropic Throttles Claude During Peak Hours Anthropic quietly adjusted usage policies for Claude subscribers, reducing service quality during peak demand windows: 05:00–11:00 PT / 13:00–19:00 GMT. Under the change, users can burn five hours' worth of usage budget in under five hours during off-peak periods but face capacity-based throttling mid-day. The policy affects all Claude tiers and highlights the ongoing challenge of matching surging demand with infrastructure capacity. Customers noticed degraded response quality before any official communication. Source: The Registerhttps://www.theregister.com/2026/03/26/anthropictweaksusagelimits/ AI-Written Code Linked to 74 CVEs Georgia Tech researchers published findings linking AI-authored code to 74 confirmed CVEs out of 43,849 security advisories analyzed between May 2025 and March 2026. The context: Claude Code alone has accumulated over 15 million public GitHub commits — roughly 4% o