Critical

Crawl4AI arbitrary file write via download filename path traversal

Type: advisorySources: OSV

Crawl4AI is an open-source LLM-friendly web crawler and scraper. Prior to 0.9.0, when the crawler saves a downloaded file, the destination filename was taken from attacker-influenced input and joined to the downloads directory with no confinement. A filename containing an absolute path or traversal escaped the downloads directory, giving an arbitrary file write with attacker-controlled contents; the HTTP crawler path uses the response Content-Disposition filename and the browser crawler path uses the download's suggested filename. Because the written bytes are attacker-controlled, this can escalate to remote code execution. This issue is fixed in version 0.9.0.

Products: Not specified
Affected versions: Not specified
Fixed versions: Not specified
CVEs: CVE-2026-57571
Confirmed fixed CVEs: Not specified
Updated in this feed: 7 Nov 2026, 00:36 UTC · Revision 1

Source evidence

Crawl4AI arbitrary file write via download filename path traversal

core-osv · Original source

Published 6 Jul 2026, 20:09 UTC

osv:CVE-2026-57571

Complete source record

{
  "id": "cc8922b4bbdb262611ee8b0f7de318edb99e540f5fcda48ce225d085d2e68e87",
  "url": "https://osv.dev/vulnerability/CVE-2026-57571",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Crawl4AI arbitrary file write via download filename path traversal",
    "summary": "Crawl4AI is an open-source LLM-friendly web crawler and scraper. Prior to 0.9.0, when the crawler saves a downloaded file, the destination filename was taken from attacker-influenced input and joined to the downloads directory with no confinement. A filename containing an absolute path or traversal escaped the downloads directory, giving an arbitrary file write with attacker-controlled contents; the HTTP crawler path uses the response Content-Disposition filename and the browser crawler path uses the download's suggested filename. Because the written bytes are attacker-controlled, this can escalate to remote code execution. This issue is fixed in version 0.9.0.",
    "evidence": "osv:CVE-2026-57571",
    "products": [],
    "severity": "critical",
    "structured": {
      "id": "CVE-2026-57571",
      "aliases": [
        "CVE-2026-57571",
        "GHSA-2jq4-q6vv-4cp3",
        "PYSEC-2026-2138"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/unclecode/crawl4ai",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "c66f3276fd355031c8632500911fe7041ad6fc14"
                },
                {
                  "fixed": "60886d1a0c52682e4c83a7cef9dfac417fff6bd2"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:kidocode:crawl4ai:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "0.9.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "60886d1a0c52682e4c83a7cef9dfac417fff6bd2"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v0.8.9",
            "docker-rebuild-v0.8.9",
            "v0.8.8",
            "docker-rebuild-v0.8.8",
            "v0.8.7",
            "docker-rebuild-v0.8.7",
            "docker-rebuild-v0.8.6",
            "v0.8.6",
            "v0.7.4",
            "v0.7.3",
            "v0.7.2",
            "v0.7.1",
            "v0.7.0",
            "vr0.6.3",
            "v0.6.3",
            "vr0.6.0",
            "vr0.6.0rc1",
            "v0.5.0.post1",
            "v0.4.243",
            "v0.4.24",
            "v0.3.745",
            "v.3.72",
            "v0.3.6",
            "0.3.4",
            "v0.3.3",
            "v0.3.0",
            "v0.2.77",
            "v0.0.75",
            "v0.2.74",
            "v0.2.73",
            "v0.2.72",
            "v0.2.71",
            "v0.2.7",
            "v0.2.6",
            "v0.2.4",
            "v0.2.1",
            "v0.2.0",
            "v0.1.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-57571.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:48.301315641Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/57xxx/CVE-2026-57571.json",
        "https://github.com/unclecode/crawl4ai/security/advisories/GHSA-2jq4-q6vv-4cp3",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-57571",
        "https://github.com/unclecode/crawl4ai/commit/60886d1a0c52682e4c83a7cef9dfac417fff6bd2"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-22",
          "CWE-59"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/57xxx/CVE-2026-57571.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-57571",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 516664,
  "published_at": "2026-07-06T20:09:52.251+00:00"
}