{"cve":"CVE-2026-85740","nvd":{"published":"2026-09-22T17:17:27.520","modified":"2026-09-28T20:17:11.063","status":"Deferred","description":"LightRAG provides simple and fast retrieval-augmented generation. Prior to 1.5.5, _validated_addresses in lightrag/parser/markdown/parser.py evaluates the literal resolved address with ipaddress.is_global without consistently classifying an IPv4 address embedded in an IPv6 transition wrapper. A caller who can upload a Markdown or textpack document can supply an external image URL using NAT64 64:ff9b::/96 or an IPv4-compatible form that embeds a loopback, private, or cloud-metadata IPv4 address. On a deployment with compatible NAT64 or DNS64 routing, _download and _build_guarded_opener accept the wrapper and fetch the internal resource, whose body is then ingested. Current interpreter behavior already blocks some RFC 8215 and 6to4 forms, but the fixed guard handles all documented wrappers without becoming more permissive than the standard library. This issue is fixed in version 1.5.5.","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/HKUDS/LightRAG/commit/9207e7fd10cf6df3cf26e3dd1921490b34a2f132","https://github.com/HKUDS/LightRAG/commit/a25862177a9b00e0edb870778a42b4155924de09","https://github.com/HKUDS/LightRAG/commit/c598545aa0084a427bcb19a84ade5e0ec31fa673","https://github.com/HKUDS/LightRAG/pull/3426","https://github.com/HKUDS/LightRAG/releases/tag/v1.5.5"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:56:02.509636177+00:00"},"epss":{"cve":"CVE-2026-85740","score":0.00264,"percentile":0.18251,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-vv3m-f8x4-7377","url":"https://osv.dev/vulnerability/GHSA-vv3m-f8x4-7377","summary":"lightrag-hku: SSRF via IPv6-transition address bypass (NAT64, IPv4-compatible, 6to4) of the native-markdown image-download guard","modified":"2026-10-01T17:56:10.193162388Z","packages":[{"ecosystem":"PyPI","name":"lightrag-hku","purl":"pkg:pypi/lightrag-hku","ranges":["<1.5.5"],"fixed":["1.5.5"]}]},{"id":"PYSEC-2026-4064","url":"https://osv.dev/vulnerability/PYSEC-2026-4064","summary":"lightrag-hku: SSRF via IPv6-transition address bypass (NAT64, IPv4-compatible, 6to4) of the native-markdown image-download guard","modified":"2026-10-01T17:45:05.558721230Z","packages":[{"ecosystem":"PyPI","name":"lightrag-hku","purl":"pkg:pypi/lightrag-hku","ranges":["<1.5.5"],"fixed":["1.5.5"]}]}],"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."]}