{"id":"CVE-2026-53755","aliases":["EUVD-2026-38567","GHSA-6qhc-x826-342c","PYSEC-2026-588"],"status":"published","title":"Crawl4AI: SSRF via proxy settings in the Docker server bypasses the crawl-URL SSRF check","description":"Crawl4AI is an open-source LLM friendly web crawler \u0026 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.","severity":{"version":"3.1","score":8.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.01577,"percentile":0.75679,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-918"],"published":"2026-06-16T21:02:55Z","modified":"2026-10-28T02:30:27Z","exploits":[{"source":"nuclei","id":"CVE-2026-53755","title":"crawl4ai \u003c 0.8.9 - Server Side Request Forgery","type":"detection template","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-53755.yaml"}],"fixes":[{"ecosystem":"PyPI","package":"crawl4ai","fixed_in":["0.8.9"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"crawl4ai","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"0.8.8"},{"fixed":"0.8.9"}]}]},{"source":"osv","ecosystem":"PyPI","package":"crawl4ai","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.8.9"}]}],"versions":["0.3.0","0.3.1","0.3.2","0.3.3","0.3.4","0.3.5","0.3.6","0.3.7","0.3.71","0.3.72","0.3.73","0.3.731","0.3.74","0.3.741","0.3.742","0.3.743","0.3.744","0.3.745","0.3.746","0.3.8","0.4.0","0.4.1","0.4.21","0.4.22","0.4.23","0.4.24","0.4.241","0.4.242","0.4.243","0.4.244","0.4.245","0.4.246","0.4.247","0.4.248","0.4.248b3","0.4.3b1","0.4.3b2","0.4.3b3","0.5.0","0.5.0.post1","0.5.0.post2","0.5.0.post3","0.5.0.post4","0.5.0.post5","0.5.0.post6","0.5.0.post7","0.5.0.post8","0.6.0","0.6.0rc1","0.6.1","0.6.2","0.6.3","0.7.0","0.7.1","0.7.2","0.7.3","0.7.4","0.7.5","0.7.6","0.7.7","0.7.8","0.8.0","0.8.5","0.8.6","0.8.7","0.8.8"]},{"source":"osv","ecosystem":"PyPI","package":"crawl4ai","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.8.9"}]}],"versions":["0.3.0","0.3.1","0.3.2","0.3.3","0.3.4","0.3.5","0.3.6","0.3.7","0.3.71","0.3.72","0.3.73","0.3.731","0.3.74","0.3.741","0.3.742","0.3.743","0.3.744","0.3.745","0.3.746","0.3.8","0.4.0","0.4.1","0.4.21","0.4.22","0.4.23","0.4.24","0.4.241","0.4.242","0.4.243","0.4.244","0.4.245","0.4.246","0.4.247","0.4.248","0.4.248b3","0.4.3b1","0.4.3b2","0.4.3b3","0.5.0","0.5.0.post1","0.5.0.post2","0.5.0.post3","0.5.0.post4","0.5.0.post5","0.5.0.post6","0.5.0.post7","0.5.0.post8","0.6.0","0.6.0rc1","0.6.1","0.6.2","0.6.3","0.7.0","0.7.1","0.7.2","0.7.3","0.7.4","0.7.5","0.7.6","0.7.7","0.7.8","0.8.0","0.8.5","0.8.6","0.8.7","0.8.8"]}],"products":[{"vendor":"kidocode","product":"crawl4ai"},{"vendor":"unclecode","product":"crawl4ai"}],"references":[{"url":"https://github.com/unclecode/crawl4ai/security/advisories/GHSA-6qhc-x826-342c","tags":["x_refsource_CONFIRM","Third Party Advisory","advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53755","tags":["advisory"]},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/crawl4ai/PYSEC-2026-588.yaml","tags":["web"]},{"url":"https://github.com/advisories/GHSA-6qhc-x826-342c"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53755.json","tags":["advisory"]},{"url":"https://github.com/unclecode/crawl4ai","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-53755","title":"Crawl4AI: SSRF via proxy settings in the Docker server bypasses the crawl-URL SSRF check","description":"Crawl4AI is an open-source LLM friendly web crawler \u0026 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.","status":"published","published":"2026-06-23T18:15:31.586Z","modified":"2026-06-26T15:01:29.554Z","cvss":[{"version":"3.1","score":8.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T14:19:59.761005Z"}],"euvd":[{"id":"EUVD-2026-38567","description":"Crawl4AI is an open-source LLM friendly web crawler \u0026 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.","status":"published","published":"2026-06-23T18:15:31Z","modified":"2026-06-26T15:01:29Z","cvss":[{"version":"3.1","score":8.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T18:20:24.495602Z"}],"ghsa":[{"id":"GHSA-6qhc-x826-342c","title":"Crawl4AI: SSRF via proxy settings in the Docker server bypasses the crawl-URL SSRF check","description":"### Summary\n\nThe 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.\n\n### Affected paths\n\n`/crawl`, `/crawl/stream`, and `/crawl/job` accept a `browser_config` (and `crawler_config`). The following all feed Chromium's egress and were unchecked:\n- `browser_config.proxy_config.server`\n- `browser_config.proxy` (deprecated field)\n- `crawler_config.proxy_config.server`\n- `--proxy-server` / `--proxy-pac-url` / `--proxy-bypass-list` / `--host-resolver-rules` flags in `browser_config.extra_args`\n\n### Attack\n\nAn attacker sends `/crawl` with a benign, validation-passing URL but a `proxy_config.server` pointing at an internal IP. Chromium routes all requests through that proxy. For plain-HTTP targets the proxy receives the full request and can return any content, which is then returned verbatim in the crawl result (`results[0].html` / `cleaned_html` / `markdown`). In a real deployment the proxy would be an attacker-controlled server pointing at cloud metadata (e.g. AWS IMDSv1 at 169.254.169.254) to retrieve IAM credential tokens.\n\n### Impact\n\nUnauthenticated server-side request forgery to internal services and cloud-metadata endpoints, with the response returned to the attacker.\n\n### Fix\n\nEvery proxy destination is validated with the same global-routability check used for crawl URLs (reject any resolved address that is not `is_global`, including IPv6 transition forms) before the browser is constructed; proxy/DNS-redirecting flags are stripped from `extra_args`. A legitimate public proxy still works. Honors `CRAWL4AI_ALLOW_INTERNAL_URLS`.\n\n### Workarounds\n\n- Upgrade to the patched version (0.8.9).\n- Enable authentication (`CRAWL4AI_API_TOKEN`).\n- Restrict the container's outbound network access (egress firewall / no metadata route).\n\n### Credits\n\nGeo ([geo-chen](https://github.com/geo-chen)) - reported the proxy_config.server SSRF with a clear PoC.","status":"published","published":"2026-06-16T21:02:55Z","modified":"2026-07-20T21:12:13Z","cvss":[{"version":"3.1","score":8.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T14:40:47.245721Z"}],"nvd":[{"id":"CVE-2026-53755","description":"Crawl4AI is an open-source LLM friendly web crawler \u0026 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.","status":"published","published":"2026-06-23T19:17:07.477Z","modified":"2026-10-25T23:10:00.167Z","cvss":[{"version":"3.1","score":8.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","level":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"primary"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T14:12:25.288279Z"}],"osv":[{"id":"CVE-2026-53755","title":"Crawl4AI: SSRF via proxy settings in the Docker server bypasses the crawl-URL SSRF check","description":"Crawl4AI is an open-source LLM friendly web crawler \u0026 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.","status":"published","published":"2026-06-23T18:15:31.586Z","modified":"2026-10-28T02:30:27.640247409Z","cvss":[{"version":"3.1","score":8.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T15:45:08.132336Z"},{"id":"GHSA-6qhc-x826-342c","title":"Crawl4AI: SSRF via proxy settings in the Docker server bypasses the crawl-URL SSRF check","description":"### Summary\n\nThe 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.\n\n### Affected paths\n\n`/crawl`, `/crawl/stream`, and `/crawl/job` accept a `browser_config` (and `crawler_config`). The following all feed Chromium's egress and were unchecked:\n- `browser_config.proxy_config.server`\n- `browser_config.proxy` (deprecated field)\n- `crawler_config.proxy_config.server`\n- `--proxy-server` / `--proxy-pac-url` / `--proxy-bypass-list` / `--host-resolver-rules` flags in `browser_config.extra_args`\n\n### Attack\n\nAn attacker sends `/crawl` with a benign, validation-passing URL but a `proxy_config.server` pointing at an internal IP. Chromium routes all requests through that proxy. For plain-HTTP targets the proxy receives the full request and can return any content, which is then returned verbatim in the crawl result (`results[0].html` / `cleaned_html` / `markdown`). In a real deployment the proxy would be an attacker-controlled server pointing at cloud metadata (e.g. AWS IMDSv1 at 169.254.169.254) to retrieve IAM credential tokens.\n\n### Impact\n\nUnauthenticated server-side request forgery to internal services and cloud-metadata endpoints, with the response returned to the attacker.\n\n### Fix\n\nEvery proxy destination is validated with the same global-routability check used for crawl URLs (reject any resolved address that is not `is_global`, including IPv6 transition forms) before the browser is constructed; proxy/DNS-redirecting flags are stripped from `extra_args`. A legitimate public proxy still works. Honors `CRAWL4AI_ALLOW_INTERNAL_URLS`.\n\n### Workarounds\n\n- Upgrade to the patched version (0.8.9).\n- Enable authentication (`CRAWL4AI_API_TOKEN`).\n- Restrict the container's outbound network access (egress firewall / no metadata route).\n\n### Credits\n\nGeo ([geo-chen](https://github.com/geo-chen)) - reported the proxy_config.server SSRF with a clear PoC.","status":"published","published":"2026-06-16T21:02:55Z","modified":"2026-07-20T21:30:33.098890697Z","cvss":[{"version":"3.1","score":8.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"cwes":["CWE-918"],"updated_at":"2026-11-02T15:46:39.965326Z"},{"id":"PYSEC-2026-588","description":"Crawl4AI is an open-source LLM friendly web crawler \u0026 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.","status":"published","published":"2026-06-23T19:17:07.477Z","modified":"2026-06-30T23:45:06.039027554Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:52:57.671918Z"}]}}