{"cve":"CVE-2026-56817","nvd":{"published":"2026-07-21T23:17:52.127","modified":"2026-07-30T14:48:18.777","status":"Analyzed","description":"Netty is a network application framework for development of protocol servers and clients. In versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final, any caller that can deliver bytes to a Netty channel pipeline containing `XmlDecoder` can send XML with a `DOCTYPE` declaration to an `AsyncXMLInputFactory` instantiated with no security configuration, leaving DTD and entity handling active depending on Aalto XML async parser behavior and creating conditional XML external entity risk. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N","score":8.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-611"],"references":["https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b","https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6","https://github.com/netty/netty/releases/tag/netty-4.1.136.Final","https://github.com/netty/netty/releases/tag/netty-4.2.16.Final","https://github.com/netty/netty/security/advisories/GHSA-4qhr-g3c6-fcfx"],"products":["netty:netty"],"source":"nvd","synced_at":"2026-10-19T22:45:53.305392138+00:00"},"epss":{"cve":"CVE-2026-56817","score":0.00694,"percentile":0.52971,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-4qhr-g3c6-fcfx","url":"https://osv.dev/vulnerability/GHSA-4qhr-g3c6-fcfx","summary":"Netty XML: Injection / Risky Sink — unconfigured XML factory with active DTD and entity handling","modified":"2026-09-10T03:50:12.356157174Z","packages":[{"ecosystem":"Maven","name":"io.netty:netty-codec-xml","purl":"pkg:maven/io.netty/netty-codec-xml","ranges":[">=4.2.0.Final <4.2.16.Final"],"fixed":["4.2.16.Final"]},{"ecosystem":"Maven","name":"io.netty:netty-codec-xml","purl":"pkg:maven/io.netty/netty-codec-xml","ranges":[">=4.1.0.Final <4.1.136.Final"],"fixed":["4.1.136.Final"]}]}],"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."]}