Credentials, surface, execution: the May 17 risk surface, 100 days later

Episode 18 of Agent Mode AI. Abby and Avery walk AM-155, AM-156 and AM-157 — the May 17 batch that the publication composed as a credentials-to-surface-to- execution chain. AM-155 reads the CSRB Storm-0558 findings forward into 2026 enterprise AI agent credential storage. AM-156 names shadow-AI detection lag as structural to the audit model, not procedural — Samsung 2023 as the recurring pattern, not a one-time incident. AM-157 walks the May 2026 Microsoft Semantic Kernel CVEs (CVE-2026-25592, CVE-2026-26030) and the MCP STDIO advisories that turn prompt injection from a model-output problem into a host-level RCE problem. The trilogy as one chain — credential exposure plus undetected surface plus framework-RCE — is what no single piece could carry alone. The episode airs 112 days after the May 17 batch, so each claim has cleared its first review cadence. The closing chapter names the three questions the trilogy added to the AI MSA red-team checklist. Sources cited: - CSRB report on Storm-0558 (2024, referenced) - Samsung internal memo coverage, 2023 - CVE-2026-25592 and CVE-2026-26030, NIST NVD - MCP STDIO advisories, Anthropic, May 2026 - Windsurf 1.9544.26 advisory - Vendor disclosures published May–September 2026 (confirmed at draft time) Claims tracked: - AM-155 — Non-human identity after the CSRB report — agentmodeai.com/holding/?claim=AM-155 - AM-156 — Shadow-AI detection lag is structural — agentmodeai.com/holding/?claim=AM-156 - AM-157 — Prompt injection crosses the RCE threshold — agentmodeai.com/holding/?claim=AM-157 Newsletter and the full Holding-up ledger: agentmodeai.com