CVE-2026-53754 json
Crawl4AI: SSRF filter bypass in Docker server via IPv6 transition forms (NAT64 / 6to4 / unspecified / v4-mapped)
published 2026-06-16 4 mo ago modified 2026-10-25 14 d ago also GHSA-4qqr-vv2q-cmr5 , PYSEC-2026-587 , EUVD-2026-38568
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 37%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- pypi crawl4ai 0.8.8
- kidocode crawl4ai 0.8.8
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 4 mo ago
Exploit prediction
0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| OSV | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | crawl4ai | <0.8.8 |
0.8.8 |
Affected products
- unclecode crawl4ai
Classification
- Weakness
-
- CWE-918 Server-Side Request Forgery
References
-
github.com
/unclecode/crawl4ai/security/advisories/GHSA-4qqr-vv2q-cmr5
web, third-party-advisory, mitigation, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-53754
advisory
-
github.com
/pypa/advisory-database/tree/main/vulns/crawl4ai/PYSEC-2026-587.yaml
web
-
github.com
/unclecode/crawl4ai
package
Sources
- CVE List CVE-2026-53754
- GitHub Advisory GHSA-4qqr-vv2q-cmr5
- NVD CVE-2026-53754
- OSV PYSEC-2026-587
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