---
id: "CVE-2026-116011"
kind: "vulnerability"
aliases: ["CVE-2026-116011"]
title: "Crow: deeply nested JSON request crashes the server process"
severity: "high"
cvss: 8.7
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["c++", "crow", "package", "poc-public", "self-hosted", "web-api"]
not_affected_if: ["no-untrusted-json-parsing", "upgraded-to-1.3.4"]
published_at: "2026-10-24T12:16:57+00:00"
first_seen_at: "2026-10-24T12:47:58+00:00"
updated_at: "2026-10-25T02:59:58+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-116011", "first_seen_at": "2026-10-24T12:47:58+00:00"}, {"source": "github-poc", "url": "https://github.com/D7EAD/CVE-2026-116011", "first_seen_at": "2026-10-24T19:23:49+00:00"}]
---

# Crow: deeply nested JSON request crashes the server process

Crow's crow::json::load() parses deeply nested JSON with unbounded recursion, so a request body with thousands of nested objects exhausts the worker thread stack. An unauthenticated remote attacker can terminate the process and drop all its connections.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the Crow version in the project's dependency manifest or vendored headers; `unknown` otherwise.
- Search the codebase for calls to `crow::json::load(` that parse request bodies.

## Fix

- Upgrade Crow to `1.3.4` or later.
- Until upgraded, reject or size-limit request bodies before calling `crow::json::load()`.

## Timeline

- 2026-10-24T12:47:58+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-116011
- 2026-10-24T19:23:49+00:00 github-poc https://github.com/D7EAD/CVE-2026-116011

## Documents

- [poc] D7EAD/CVE-2026-116011 https://github.com/D7EAD/CVE-2026-116011

## From the sources

Crow before 1.3.4 contains an uncontrolled recursion vulnerability in crow::json::load() that allows remote unauthenticated attackers to crash the server by sending deeply nested JSON. Attackers can send a request body with thousands of nested objects to exhaust the worker thread stack, terminating the process and dropping all connections.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_