CVE-2026-53755 Crawl4AI: SSRF via proxy settings in the Docker server bypasses the crawl-URL SSRF check
Unauthenticated attackers can bypass SSRF checks by specifying malicious proxy settings in Crawl4AI Docker API requests, accessing internal services and cloud metadata.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-53755?
CVE-2026-53755 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 0.8.9, the Docker API server applied its SSRF destination check to the crawl target URL only, not to the proxy address. An unauthenticated request could supply a proxy pointing at an internal IP and route the browser through it, reaching internal services and cloud-metadata endpoints, while using a perfectly valid crawl URL. The Docker API is unauthenticated by default. /crawl, /crawl/stream, and /crawl/job accept a browser_config (and crawler_config). The following all feed Chromium's egress and were unchecked: browser_config.proxy_config.server, browser_config.proxy (deprecated field), crawler_config.proxy_config.server, and --proxy-server / --proxy-pac-url / --proxy-bypass-list / --host-resolver-rules flags in browser_config.extra_args. This vulnerability is fixed in 0.8.9.
Weakness: CWE-918
Which versions are affected by CVE-2026-53755?
3 open source packages ship an affected version, including crawl4ai. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
crawl4ai PyPI | All versions | 0.8.9 |
crawl4ai PyPI | All versions | 0.8.9 |
crawl4ai PyPI | All versions | 0.8.9 |
Products include Kidocode Crawl4ai.
How do I fix CVE-2026-53755?
Upgrade crawl4ai to 0.8.9 or later.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-53755 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-53755 exists.
Public exploit code: 1 Nuclei template.
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-6qhc-x826-342c, PYSEC-2026-588.