CVE-2026-84364

The record

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.13.5, when parseBody() expands dot-separated form field names into nested objects with dot-notation parsing enabled, it does not limit the nesting depth or the total number of intermediate objects created. Empty segments are preserved, so one deeply dotted field name can encode one nesting level per byte, while a large number of shallowly dotted fields can create the same amplification across a request. A request body within a normal size limit can therefore allocate an object graph far larger than the request after the body has already been accepted. An unauthenticated attacker who can reach an affected endpoint can send concurrent requests that exhaust the JavaScript heap, terminate the server process, and leave the service unavailable until restart. Dot-notation parsing is not enabled by default, and applications using the default behavior are not affected. This issue is fixed in version 4.13.5.

Affected packages

Related vulnerabilities

• CVE-2026-113795 pypdf is a free and open-source pure-python PDF library. CWE-400
• CVE-2026-83400 Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise… CWE-400
• CVE-2026-112400 Pillow is a Python imaging library. CWE-400
• CVE-2026-111766 markdown-it is a Markdown parser. CWE-400
• CVE-2026-111759 markdown-it is a Markdown parser. CWE-400
• CVE-2025-52290 A NULL pointer dereference in the avpriv_h264_has_num_reorder_frames function of Ffmpeg… CWE-400
• CVE-2026-111066 AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. CWE-400
• CVE-2026-59951 The MCP Python SDK, called mcp on PyPI, is a Python implementation of the Model Context… CWE-400