{"id":"CVE-2026-59903","aliases":["GHSA-8c42-7qj2-3j46"],"url":"https://o3.security/vulnerability/CVE-2026-59903","summary":"Netty: Cache Poisoning and Information Disclosure via CORS Vary Header Overwrite","details":"Netty is an asynchronous, event-driven network application framework. Prior to 4.1.137.Final and 4.2.17.Final, io.netty.handler.codec.http.cors.CorsHandler setVaryHeader replaces application Vary headers such as Authorization or Cookie with Origin, allowing a caching proxy or CDN to reuse authenticated responses across users and disclose sensitive information. This issue is fixed in versions 4.1.137.Final and 4.2.17.Final.","published":"2026-08-17T17:56:28.726Z","modified":"2026-08-19T03:48:26.168385646Z","cvss":{"score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Maven","name":"io.netty:netty-codec-http","fixedVersion":"4.2.17.Final"},{"ecosystem":"Maven","name":"io.netty:netty-codec-http","fixedVersion":"4.1.137.Final"}],"fix":{"url":"https://github.com/netty/netty/pull/17213","label":"netty/netty#17213"},"references":[{"type":"WEB","url":"https://github.com/netty/netty/releases/tag/netty-4.1.137.Final"},{"type":"WEB","url":"https://github.com/netty/netty/releases/tag/netty-4.2.17.Final"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59903.json"},{"type":"ADVISORY","url":"https://github.com/netty/netty/security/advisories/GHSA-8c42-7qj2-3j46"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-59903"},{"type":"FIX","url":"https://github.com/netty/netty/pull/17213"},{"type":"FIX","url":"https://github.com/netty/netty/pull/17217"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-19T03:48:26.168385646Z"}}