Vulnerability · Published Nov 5, 2026 · Assigned by GitHub_M
CVE-2026-111768Model Context Protocol TypeScript SDK: One HTTP request within the default size limit could exhaust server memory during validation
High 7.5
In plain English
A high-severity resource allocation without limits in sdk from @modelcontextprotocol. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
The Model Context Protocol TypeScript SDK provides TypeScript client and server implementations of the Model Context Protocol. From 1.3.0 until 1.32.0 in @modelcontextprotocol/sdk and from 2.0.0 until 2.3.0 in @modelcontextprotocol/server, HTTP servers did not enforce a limit on the number of array elements and object keys validated in one request. The affected surface is validation of HTTP requests containing arrays or object keys. The trigger is an array-element or object-key validation workload large enough to exhaust memory while remaining within the request size limit. A single request within the default 4 MiB limit can terminate the process with JavaScript heap exhaustion. No credentials are required unless the application authenticates before SDK processing. Tools accepting arrays or records carry the greatest risk. stdio-only servers do not expose the HTTP request path. Upgrading alone does not enable the new validation bound. Operators must configure both a tool-input element bound and an appropriate request body size limit. This issue is fixed in @modelcontextprotocol/sdk 1.32.0 and @modelcontextprotocol/server 2.3.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @modelcontextprotocol/sdk | 1.32.0 | GHSA-46jr-4wx8-v453 |
| npm | @modelcontextprotocol/server | 2.3.0 | GHSA-46jr-4wx8-v453 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| modelcontextprotocol | typescript-sdk | >= 1.3.0, < 1.32.0 |
| @modelcontextprotocol | server | >= 2.0.0, < 2.3.0 |
| @modelcontextprotocol | sdk | >= 1.3.0, < 1.32.0 |
Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-46jr-4wx8-v453 x_refsource_CONFIRM
- https://github.com/modelcontextprotocol/typescript-sdk/pull/2926 x_refsource_MISC
- https://github.com/modelcontextprotocol/typescript-sdk/pull/2927 x_refsource_MISC
- https://github.com/modelcontextprotocol/typescript-sdk/commit/6d8dbc6cb590edf766fcb66b636ca6b654e99c37 x_refsource_MISC
- https://github.com/modelcontextprotocol/typescript-sdk/commit/fd26801b3b387742fe24a90ed4b275dd6072209f x_refsource_MISC
- https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/1.32.0 x_refsource_MISC
- https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/@modelcontextprotocol/server@2.3.0 x_refsource_MISC