{"data":{"id":"2ea2f097-3045-4451-a1e7-8aa372b0e927","title":"Opus 4.6 and Codex 5.3","summary":"Anthropic released Opus 4.6 and OpenAI released GPT-5.3-Codex (currently available only through the Codex app, not via API) as major new model releases. While both models perform well, they show only incremental improvements over their predecessors (Opus 4.5 and Codex 5.2), with one notable demonstration being the ability to build a C compiler (a program that translates code into machine instructions) using multiple parallel instances of Claude working together.","solution":"N/A -- no mitigation discussed in source.","labels":["industry"],"sourceUrl":"https://simonwillison.net/2026/Feb/5/two-new-models/#atom-everything","publishedAt":"2026-02-05T20:29:20.000Z","cveId":null,"cweIds":null,"cvssScore":null,"cvssSeverity":null,"severity":"info","attackType":[],"issueType":"news","affectedPackages":null,"affectedVendors":["Anthropic","OpenAI"],"affectedVendorsRaw":["Anthropic","Opus 4.6","OpenAI","GPT-5.3-Codex","Codex","Nicholas Carlini","Claude"],"classifierModel":"claude-haiku-4-5-20251001","classifierPromptVersion":"v3","cvssVector":null,"attackVector":null,"attackComplexity":null,"privilegesRequired":null,"userInteraction":null,"exploitMaturity":null,"epssScore":null,"patchAvailable":null,"disclosureDate":null,"capecIds":null,"crossRefCount":0,"attackSophistication":"moderate","impactType":null,"aiComponentTargeted":"model","llmSpecific":true,"classifierConfidence":0.85,"researchCategory":null,"atlasIds":null}}