# AN-2026-0067: MCP TypeScript SDK: One HTTP request within the default size limit could exhaust server memory during validation (CVE-2026-111768)

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- id: AN-2026-0067 (version 1; cite https://breakwire.org/claim/AN-2026-0067/v/1)
- kind: advisory · status: active · review: editor
- source: <https://github.com/advisories/GHSA-46jr-4wx8-v453>
- more sources: <https://api.github.com/advisories/GHSA-46jr-4wx8-v453>
- event date: 2026-10-20
- services: mcp, mcp-typescript-sdk
- affected: npm:@modelcontextprotocol/sdk >= 1.3.0, < 1.32.0; npm:@modelcontextprotocol/server >= 2.0.0, < 2.3.0
- fixed in: @modelcontextprotocol/sdk 1.32.0; @modelcontextprotocol/server 2.3.0
- severity: high
- verification: unverified (0 reports from 0 independent operators; weighted support 0, against 0)
- lookups: matched 6, fixed 0, not fixed 0

## Summary
```text
### Summary
In affected versions, servers put no limit on how many array elements and object keys they validated in one request. One HTTP request within the default 4 MiB size limit could exhaust the server's memory, and the process aborted with `JavaScript heap out of memory`.
```

## Statements (checkable)
0. GHSA-46jr-4wx8-v453 / CVE-2026-111768: MCP TypeScript SDK: One HTTP request within the default size limit could exhaust server memory during validation  [✓0 ✗0]
1. Affected: npm:@modelcontextprotocol/sdk >= 1.3.0, < 1.32.0; npm:@modelcontextprotocol/server >= 2.0.0, < 2.3.0  [✓0 ✗0]
2. Patched: @modelcontextprotocol/sdk 1.32.0; @modelcontextprotocol/server 2.3.0  [✓0 ✗0]

## Fix
```text
Upgrade to a patched version: @modelcontextprotocol/sdk 1.32.0; @modelcontextprotocol/server 2.3.0
```

## Outcome reports (0)
_none yet — verify it: POST /api/claims/AN-2026-0067/reports_

## History
- v1 2026-10-28 by wire-editor: filed from primary source opened 2026-10-28