{"cve":"CVE-2026-55787","nvd":{"published":"2026-10-14T19:17:17.927","modified":"2026-10-16T20:04:29.760","status":"Deferred","description":"Flyto2 Core is an execution kernel for automation and AI-agent workflows. Prior to 2.26.3, validate_url_ssrf and is_private_ip in src/core/utils.py compare resolved addresses only against native private IPv4 and IPv6 ranges and do not unwrap IPv4-mapped, IPv4-compatible, 6to4, or NAT64 transition addresses. An authenticated workflow author can provide a transition-form literal URL through the Execution API POST /v1/execute route, http.get, or sibling guarded outbound-request modules, causing the guard to accept an address whose embedded IPv4 points to loopback, RFC 1918, or cloud metadata services. On a host that routes the selected transition form, the outbound request reaches the internal destination and returns the response body to the workflow caller, enabling read SSRF and disclosure of internal-service data or cloud credentials. This issue is fixed in version 2.26.3.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N","score":7.1},"cwes":["CWE-918"],"references":["https://github.com/flytohub/flyto-core/commit/519e040384a74984848c4e84a6600e5f1020a6d2","https://github.com/flytohub/flyto-core/pull/20","https://github.com/flytohub/flyto-core/releases/tag/v2.26.3","https://github.com/flytohub/flyto-core/security/advisories/GHSA-794r-5rp2-fpg8","https://github.com/flytohub/flyto-core/security/advisories/GHSA-794r-5rp2-fpg8"],"products":[],"source":"nvd","synced_at":"2026-10-19T23:00:53.604569364+00:00"},"epss":{"cve":"CVE-2026-55787","score":0.00292,"percentile":0.21574,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-794r-5rp2-fpg8","url":"https://osv.dev/vulnerability/GHSA-794r-5rp2-fpg8","summary":"flyto-core has SSRF guard bypass via IPv6 transition addresses (IPv4-mapped / 6to4 / NAT64) in validate_url_ssrf","modified":"2026-07-13T16:42:32.624171385Z","packages":[{"ecosystem":"PyPI","name":"flyto-core","purl":"pkg:pypi/flyto-core","ranges":["<2.26.3"],"fixed":["2.26.3"]}]},{"id":"PYSEC-2026-2481","url":"https://osv.dev/vulnerability/PYSEC-2026-2481","summary":"flyto-core has SSRF guard bypass via IPv6 transition addresses (IPv4-mapped / 6to4 / NAT64) in validate_url_ssrf","modified":"2026-07-13T16:31:47.492722881Z","packages":[{"ecosystem":"PyPI","name":"flyto-core","purl":"pkg:pypi/flyto-core","ranges":["<2.26.3"],"fixed":["2.26.3"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}