---
title: "CVE-2026-56266: Crawl4AI: Multiple Docker API Vulnerabilities - File Write, SSRF, Auth Bypass, XSS, JS Execution"
url: https://erroneo.us/security/cve/CVE-2026-56266/
description: "CVE-2026-56266 (crawl4ai (PyPI)): Crawl4AI before 0.8.7 contains a server-side request forgery vulnerability in the /crawl, /crawl/stream, /md, and /llm…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-06-22
date_modified: 2026-09-23
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-56266"
kev: false
cvss: 9.2
epss: 0.00476
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-56266: Crawl4AI: Multiple Docker API Vulnerabilities - File Write, SSRF, Auth Bypass, XSS, JS Execution

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.5% , percentile 40: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 40% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes crawl4ai (PyPI) <= 0.8.6, fixed in 0.8.7 . Check your lockfile, including transitive dependencies.

## What it is

Crawl4AI before 0.8.7 contains a server-side request forgery vulnerability in the /crawl, /crawl/stream, /md, and /llm endpoints that fetch arbitrary user-supplied URLs without validation. Unauthenticated attackers can bypass the internal-address blocklist using IPv6-mapped IPv4 addresses to reach internal services and cloud metadata endpoints.

## Affected packages

- PyPI `crawl4ai` <= 0.8.6 → fixed: 0.8.7

## Affected products (CVE record)

- Crawl4AI Crawl4AI: < 0.8.7

## Severity

- VulnCheck CVSS 4.0: 9.2 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N`
- VulnCheck CVSS 3.1: 8.6 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N`
- GitHub CVSS 4.0: 9.2 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.48% probability of exploitation activity in the next 30 days; percentile 40.

## Sources

- [Vendor advisory (github.com)](https://github.com/unclecode/crawl4ai/security/advisories/GHSA-365w-hqf6-vxfg)
- [GitHub Advisory GHSA-365w-hqf6-vxfg](https://github.com/advisories/GHSA-365w-hqf6-vxfg)
- [CVE.org record CVE-2026-56266](https://www.cve.org/CVERecord?id=CVE-2026-56266)
- [NVD entry CVE-2026-56266](https://nvd.nist.gov/vuln/detail/CVE-2026-56266)
- [github.com](https://github.com/unclecode/crawl4ai)
- [VulnCheck Advisory: Crawl4AI - Server-Side Request Forgery via Direct Crawl Endpoints](https://www.vulncheck.com/advisories/crawl4ai-server-side-request-forgery-via-direct-crawl-endpoints)
- [vulncheck.com](https://www.vulncheck.com/advisories/crawl4ai-unauthenticated-access-to-monitor-endpoints-via-docker-api-server)
- [vulncheck.com](https://www.vulncheck.com/advisories/crawl4ai-stored-cross-site-scripting-in-monitor-dashboard)
- [vulncheck.com](https://www.vulncheck.com/advisories/crawl4ai-server-side-request-forgery-via-webhook-urls)
- [vulncheck.com](https://www.vulncheck.com/advisories/crawl4ai-authentication-bypass-via-hardcoded-jwt-signing-key)
- [vulncheck.com](https://www.vulncheck.com/advisories/crawl4ai-arbitrary-javascript-execution-via-execute-js-endpoint)
- [vulncheck.com](https://www.vulncheck.com/advisories/crawl4ai-arbitrary-file-write-via-output-path-parameter)
- [github.com](https://github.com/pypa/advisory-database/tree/main/vulns/crawl4ai/PYSEC-2026-798.yaml)
- [github.com](https://github.com/pypa/advisory-database/tree/main/vulns/crawl4ai/PYSEC-2026-596.yaml)
- [github.com](https://github.com/pypa/advisory-database/tree/main/vulns/crawl4ai/PYSEC-2026-3449.yaml)
- [github.com](https://github.com/pypa/advisory-database/tree/main/vulns/crawl4ai/PYSEC-2026-3443.yaml)
- [github.com](https://github.com/pypa/advisory-database/tree/main/vulns/crawl4ai/PYSEC-2026-239.yaml)
- [github.com](https://github.com/pypa/advisory-database/tree/main/vulns/crawl4ai/PYSEC-2026-230.yaml)
- [github.com](https://github.com/pypa/advisory-database/tree/main/vulns/crawl4ai/PYSEC-2026-229.yaml)
- [github.com](https://github.com/advisories/GHSA-xrfj-6m49-wfmm)
- [github.com](https://github.com/advisories/GHSA-g2pv-76hm-j4x9)
- [github.com](https://github.com/advisories/GHSA-8qrg-7j2f-rf2h)
- [github.com](https://github.com/advisories/GHSA-53rg-46cm-4g2v)
- [github.com](https://github.com/advisories/GHSA-r9hw-78q5-478g)
- [github.com](https://github.com/advisories/GHSA-f23g-2f38-gg94)

---
Source page: https://erroneo.us/security/cve/CVE-2026-56266/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt