{"cve":"CVE-2026-59903","nvd":{"published":"2026-08-17T18:17:36.250","modified":"2026-09-23T15:21:27.670","status":"Analyzed","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","score":7.5},"cwes":["CWE-524"],"references":["https://github.com/netty/netty/pull/17213","https://github.com/netty/netty/pull/17217","https://github.com/netty/netty/releases/tag/netty-4.1.137.Final","https://github.com/netty/netty/releases/tag/netty-4.2.17.Final","https://github.com/netty/netty/security/advisories/GHSA-8c42-7qj2-3j46"],"products":["netty:netty"],"source":"nvd","synced_at":"2026-10-19T22:49:10.689564601+00:00"},"epss":{"cve":"CVE-2026-59903","score":0.00324,"percentile":0.25424,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-8c42-7qj2-3j46","url":"https://osv.dev/vulnerability/GHSA-8c42-7qj2-3j46","summary":"Netty Vulnerable to Cache Poisoning and Information Disclosure via CORS Vary Header Overwrite","modified":"2026-09-10T03:51:13.389261985Z","packages":[{"ecosystem":"Maven","name":"io.netty:netty-codec-http","purl":"pkg:maven/io.netty/netty-codec-http","ranges":[">=4.2.0.Final <4.2.17.Final"],"fixed":["4.2.17.Final"]},{"ecosystem":"Maven","name":"io.netty:netty-codec-http","purl":"pkg:maven/io.netty/netty-codec-http","ranges":["<4.1.137.Final"],"fixed":["4.1.137.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."]}