Issue #265

Monday · June 15, 2026

๐Ÿฅ– Palate Cleanser

This week's drama llama gave us AWS Bedrock quietly breaking its own core promise. On June 9 Anthropic launched its new flagship Claude models, Fable 5 and Mythos 5, and AWS lit them up on Bedrock the same day. The catch, buried in the docs, is that the only way to use them is to let your prompts and outputs leave the AWS boundary and go to Anthropic, where they are kept for up to 30 days and can be read by humans. Bedrock's longstanding promise that model providers never see your prompts and completions, and that invocations stay inside the AWS network, is gone for these two models.

Chris Farris fired the first shot on June 10 with "AWS Destroyed the Value Proposition for Bedrock" (in Chef's Selections), and the reaction was loud. A 400+ point Hacker News thread, EU data-residency alarm, and Microsoft reportedly pulling Fable 5 from internal Copilot use over the same retention policy. Worth keeping the headline honest, though. The change is scoped to the new Mythos-class models, not Opus 4.8, Sonnet, or Haiku, which keep their existing zero-retention behavior, and accounts pinned to zero data retention simply have these model calls blocked rather than silently sharing data. AWS also says the data leaves its boundary while Anthropic says it stays in AWS, which might be reconcilable but not a great look. Then on June 12 the whole debate got overtaken: Anthropic disabled both models globally to comply with a US export-control directive restricting foreign-national access. So for now this is a fight about Bedrock's direction rather than a live buying decision.

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๐Ÿ“‹ Chef's selections

  • AWS Destroyed the Value Proposition for Bedrock by Chris Farris

    For the new flagship Claude models (Fable 5, Mythos 5) on AWS Bedrock, the only "allowed_mode" is "provider_data_share". That means prompts and outputs are shared with and retained by Anthropic for 30 days with human review access. This turns Bedrock from a neutral broker that shielded customer data into "first-party Anthropic," with real data-residency and CLOUD Act exposure, and no advance warning for compliance teams.

  • Blinding the Watchmen: Abusing Cloud Logging Services for Defense Evasion and Visibility by Yahav Festinger

    StopLogging is the most direct way to kill CloudTrail, so Yahav catalogues the quieter techniques like repointing a trail at an attacker-controlled KMS key with UpdateTrail then revoking CloudTrail's access so logs silently stop landing in S3, and redirecting log delivery to an attacker's own account for persistent visibility. The AWS content is mostly well-trodden ground I mapped years ago in Disrupting AWS logging, which goes deeper (KMS-immutable deletion, bucket-policy denial, S3 lifecycle auto-expiry, and Lambda-driven log deletion).

  • Phishing for Lobsters: How We Tricked OpenClaw into Spilling Secrets by Itay Yashar

    Enterprises are wiring AI agents straight into the inbox to triage and reply to mail, so Itay built one ("Pinchy") on a real Google Workspace mailbox to test whether decades-old phishing tricks still land on a machine. They do. Even with a hardened "Strict" security profile that explicitly told it to verify identities first, an urgent "Dan needs staging access" email citing a production emergency got the agent to forward AWS IAM keys, database connection strings, and SSH credentials to an external Gmail. The piece draws a sharp line between this and indirect prompt injection, and shows agents are good at spotting technical tells like malicious OAuth redirect URIs but fall for the same social pretexts that fool humans.

๐Ÿฅ— AWS security blogs

๐Ÿ› Reddit threads on r/aws


๐Ÿค– Dessert

Every machine-tracked change this week. Nobody else assembles this.

๐Ÿง IAM permission changes

๐Ÿช API changes

๐Ÿน IAM managed policy changes

    No changes this week.

โ˜• CloudFormation resource changes

๐ŸŽฎ Amazon Linux vulnerabilities

๐Ÿ“บ AWS security bulletins

๐Ÿšฌ Security documentation changes

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