{"id":"INC-anthropic-t33dncr5ydvl","kind":"incident","aliases":[],"related":[],"title":"Anthropic: Elevated errors for Claude Mythos 5.1 and Claude Fable 5.1","description":"The issue affecting Claude services has been resolved. Impact occurred from 13:57 to 14:20 UTC","summary":null,"severity":"high","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[{"name":"Anthropic","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["ai","anthropic","incident","llm","ops","vendor"],"not_affected_if":[],"how_to_check":null,"fix":null,"status":"resolved","published_at":"2026-09-11T14:19:51+00:00","first_seen_at":"2026-10-23T19:12:22+00:00","triaged_at":"2026-10-23T21:50:49+00:00","updated_at":"2026-10-23T21:50:49+00:00","category":"vendor","confidence":null,"triage":null,"analyst_status":null,"analyst_note":null,"search":"'13':34C '14':37C '20':38C '5.1':7A,11A '57':35C 'affect':25C 'ai':17B 'anthrop':1A,18B 'anthropic':14A,16A 'claud':5A,9A,26C 'elev':2A 'error':3A 'fabl':10A 'impact':31C 'inc':13A 'inc-anthropic-t33dncr5ydvl':12A 'incid':19B 'issu':24C 'llm':20B 'mytho':6A 'occur':32C 'op':21B 'resolv':30C 'servic':27C 't33dncr5ydvl':15A 'utc':39C 'vendor':22B","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2026-09-11T14:19:51+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"statuspage","external_id":"anthropic:t33dncr5ydvl","url":"https://stspg.io/n9n8kfcxtkfm","severity":"high","published_at":"2026-09-11T14:19:51+00:00","modified_at":"2026-09-11T14:37:11+00:00","first_seen_at":"2026-10-23T19:12:22+00:00","fetched_at":"2026-10-26T09:53:50+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}