CVE-2026-53754 Crawl4AI: SSRF filter bypass in Docker server via IPv6 transition forms (NAT64 / 6to4 / unspecified / v4-mapped)
Attackers can bypass SSRF filters in the Crawl4AI Docker server to access internal services and cloud metadata endpoints without authentication.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-53754?
CVE-2026-53754 is a high-severity server-side request forgery vulnerability in unclecode crawl4ai, published on 23 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Crawl4AI is an open-source LLM friendly web crawler & scraper. Prior to 0.8.8, the Docker API server's SSRF protection (validate_webhook_url / validate_url_destination in deploy/docker/utils.py) used an explicit IPv4/IPv6 CIDR blocklist that missed several address families. An attacker could reach internal services and cloud metadata endpoints (e.g. 169.254.169.254) despite the filter by encoding an internal IPv4 address inside an IPv6 transition form, or by using the IPv6 unspecified address. Because the Docker API is unauthenticated by default (jwt_enabled: false), no credentials are required. This vulnerability is fixed in 0.8.8.
Weakness: CWE-918
Which versions are affected by CVE-2026-53754?
3 open source packages ship an affected version, including crawl4ai. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
crawl4ai PyPI | All versions | 0.8.8 |
crawl4ai PyPI | All versions | 0.8.8 |
crawl4ai PyPI | All versions | 0.8.8 |
Products include Kidocode Crawl4ai.
How do I fix CVE-2026-53754?
Upgrade crawl4ai to 0.8.8 or later.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-53754 being exploited?
There is no known exploitation of CVE-2026-53754 in the wild and no public exploit code.
Other vulnerabilities in unclecode crawl4ai
- CVE-2026-57572 Crawl4AI: Unauthenticated RCE via Chromium launch-argument injection in browser_config.extra_args
- CVE-2026-26216 Crawl4AI < 0.8.0 Docker API Unauthenticated Remote Code Execution via Hooks Parameter
- CVE-2026-53753 Crawl4AI: AST Sandbox Escape via gi_frame.f_back Chain - Pre-Auth RCE in Docker API
- CVE-2026-57571 Crawl4AI arbitrary file write via download filename path traversal
- CVE-2026-56265 Crawl4AI - Authentication Bypass via Hardcoded JWT Signing Key
Sources
Also known as GHSA-4qqr-vv2q-cmr5, PYSEC-2026-587.