---
id: "CVE-2026-115508"
kind: "vulnerability"
aliases: ["CVE-2026-115508"]
title: "Crawl4AI: unbounded regex in Docker API lets authenticated clients freeze server"
severity: "high"
cvss: 7.1
epss: 0.00305
exploited: false
status: "open"
category: "ai-tooling"
products: []
ecosystems: []
tags: ["ai-tooling", "crawl4ai", "docker", "python", "self-hosted"]
not_affected_if: ["library-only-use", "no-docker-api-exposure"]
published_at: "2026-10-22T20:17:06+00:00"
first_seen_at: "2026-10-23T21:57:32+00:00"
updated_at: "2026-10-25T03:31:23+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-115508", "first_seen_at": "2026-10-23T21:57:32+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-115508", "first_seen_at": "2026-10-24T07:15:51+00:00"}]
---

# Crawl4AI: unbounded regex in Docker API lets authenticated clients freeze server

Crawl4AI's Docker API server accepts unbounded regular expressions in /crawl request bodies, and a crafted pattern causes catastrophic backtracking. An authenticated API client can freeze the entire server, including the /health endpoint.

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

## How to check

- Check the installed Crawl4AI version with `pip show crawl4ai` or the image tag of the Docker deployment; affected versions are `0.7.0` up to but not including `0.9.5`.
- Look for exposed Crawl4AI Docker API endpoints that accept `/crawl` requests from clients outside the trusted team.

## Fix

- Upgrade Crawl4AI to `0.9.5` or later, including the Docker image.
- Until upgraded, restrict who can call the `/crawl` endpoint and limit API client credentials.

## Timeline

- 2026-10-23T21:57:32+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-115508
- 2026-10-24T07:15:51+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-115508

## From the sources

Crawl4AI 0.7.0 before 0.9.5 contains an inefficient regular expression complexity vulnerability in the Docker API server that allows authenticated API clients to supply unbounded regular expressions in /crawl request bodies. Attackers can submit catastrophic-backtracking patterns via RegexExtractionStrategy.custom, RegexChunking.patterns or JsonCss, JsonXPath and JsonLxml schema regex fields against a crafted page to freeze the entire server, including /health.

---

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