# MCP resumed state changes authorization or request meaning

An MRTR server trusts modified or context-mismatched requestState when it affects a protected resumed operation.

**Candidate CWE:** [CWE-345](https://cwe.mitre.org/data/definitions/345.html) · [CWE-863](https://cwe.mitre.org/data/definitions/863.html)

## Test hypothesis

In a version-matched local fixture, compare untouched state with a single alteration, cross-principal state and changed originating arguments. Exercise a harmless protected operation.

## Evidence required

Preserve protocol/version, state digest, issuer and presenting principals, original/resumed argument digests, validation result and unauthorized stub effect.

## Rule out false positives

A parser failure, state that affects only request failure, or an implementation using another protocol era is not this finding. Do not assume client instructions to keep state opaque constrain a hostile client.

## Playbook and command references

- [AI state: memory, resumed work, retries and private caches](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/modules/ai-state-lifecycle.html) — Test persistent context, task ownership, MCP request-state integrity, duplicate effects and caches across identities and time.
- [AI tools: input trust, execution identity and approvals](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/modules/ai-tool-trust.html) — Prove when lower-trust content changes a protected tool action, then locate the missing authorization or consent boundary.

[Find the associated command snippets](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/commands.html?q=AI%20state%3A%20memory%2C%20resumed%20work%2C%20retries%20and%20private%20caches)

## Referenced by these target playbooks

[AI, agents & MCP](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/ai.html) · [OSS & self-hosted](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/oss.html)

## Report checklist

- [ ] Capture the affected version, configuration, identities, and object ownership.
- [ ] Preserve a valid baseline and a negative control.
- [ ] Reproduce the forbidden data access, action, or state change on controlled fixtures.
- [ ] Explain the intended security rule and why the observed behavior violates it.
- [ ] State prerequisites, uncertainty, cleanup, and the smallest demonstrated impact.

## Conditional ATT&CK mapping

No direct ATT&CK mapping selected. Record the weakness and demonstrated impact without forcing an adversary-behavior classification. See the [mapping guide](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/attack.html).

## Primary references

- [MCP 2026-07-28 multi round-trip requests](https://modelcontextprotocol.io/specification/2026-07-28/basic/patterns/mrtr)

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