{"type":"post","id":"microsoft-publishes-two-studies-on-post-training-supply-edd99e","slug":"microsoft-publishes-two-studies-on-post-training-supply-edd99e","title":"Microsoft publishes two studies on post-training supply chain backdoors in coding agents","description":"Microsoft Security Research and the Microsoft AI Red Team describe two ways post-training artifacts can carry dormant backdoors into coding agents: poisoned fine-tuning data and attacker-trained model checkpoints.","retrieval_nugget":"Microsoft Security Research and the Microsoft AI Red Team describe two ways post-training artifacts can carry dormant backdoors into coding agents: poisoned fine-tuning data and attacker-trained model checkpoints.","published_at":"2026-11-12","updated_at":"2026-11-12","record_date":"2026-11-12","date_kind":"published_at","topics":["coding-agents","claude"],"entities":["Microsoft","Microsoft Defender Research","Microsoft AI Red Team","gpt-4.1-mini","Qwen3.5-4B","Qwen3.5-9B","Claude Code","Codex CLI"],"related_patterns":["agent-security-moves-to-runtime-boundaries"],"novelty_label":"new_fact","what_changed":"Microsoft publishes research on post-training supply-chain attacks that can hijack coding agents, adding a distinct attack pathway to prior findings on dormant-neuron backdoors and pretraining poisoning.","prior_refs":["https://newruntime.com/posts/lazare-veni-foras-reprogramming-dormant-neurons-to-backdoor-022e16/","https://newruntime.com/posts/agentic-backdoors-via-pretraining-poisoning-0-1-poisoned-37b86e/"],"source_url":"https://www.microsoft.com/en-us/security/blog/2026/11/12/trained-to-betray-how-post-training-supply-chain-attacks-hijack-coding-agents","source_urls":["https://www.microsoft.com/en-us/security/blog/2026/11/12/trained-to-betray-how-post-training-supply-chain-attacks-hijack-coding-agents"],"schema_version":"newruntime-agent-readable-v0.2","stable_id":"post:microsoft-publishes-two-studies-on-post-training-supply-edd99e","status":"published","visuals":[],"editor":{"role":"editor","name":"Andrey Reshetnikov","profile":"https://newruntime.com/owner-profile.md","profile_json":"https://newruntime.com/owner-profile.json","same_as":["https://www.linkedin.com/in/reshetnikov1/","https://t.me/lapetuse"]},"routes":{"html":"https://newruntime.com/posts/microsoft-publishes-two-studies-on-post-training-supply-edd99e/","markdown":"https://newruntime.com/posts/microsoft-publishes-two-studies-on-post-training-supply-edd99e.md","json":"https://newruntime.com/posts/microsoft-publishes-two-studies-on-post-training-supply-edd99e.json"},"markdown_url":"https://newruntime.com/posts/microsoft-publishes-two-studies-on-post-training-supply-edd99e.md","next_reads":[{"type":"topic","path":"/topics/coding-agents/","url":"https://newruntime.com/topics/coding-agents/","title":"Coding Agents","reason":"Explore the coding-agents topic hub.","media_type":"text/html","markdown_url":"https://newruntime.com/topics/coding-agents.md","json_url":"https://newruntime.com/topics/coding-agents.json"},{"type":"topic","path":"/topics/claude/","url":"https://newruntime.com/topics/claude/","title":"Claude","reason":"Explore the claude topic hub.","media_type":"text/html","markdown_url":"https://newruntime.com/topics/claude.md","json_url":"https://newruntime.com/topics/claude.json"},{"type":"collection","path":"/posts/","url":"https://newruntime.com/posts/","title":"Field Notes","reason":"Open the latest editorial analysis.","media_type":"text/html","json_url":"https://newruntime.com/posts.json"},{"type":"collection","path":"/sources/","url":"https://newruntime.com/sources/","title":"Sources","reason":"See the original sources this archive cites.","media_type":"text/html"}]}