{"cve":"CVE-2026-59920","nvd":{"published":"2026-07-29T18:16:56.757","modified":"2026-08-06T20:34:47.847","status":"Analyzed","description":"Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.136.Final and 4.2.16.Final, Netty's STOMP encoder ( StompSubframeEncoder ) does not escape or validate header values in  CONNECT  and  CONNECTED  frames, so raw newline ( \\n ) characters in a header value are written directly to the wire, allowing an attacker who controls a header value to inject additional STOMP headers. This happens because the encoder intentionally skips escaping for CONNECT/CONNECTED frames per the STOMP 1.2 specification but never rejects the raw newlines, and since a broker parses each line as a separate header, an attacker controlling a value such as a user-supplied login or passcode can overwrite connection parameters or add authentication/role headers to bypass authentication or escalate privileges (the actual impact is broker-dependent). The issue is fixed in versions 4.1.136.Final and 4.2.16.Final.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","score":6.5},"cwes":["CWE-93"],"references":["https://github.com/netty/netty/security/advisories/GHSA-3g8r-4pfx-jmfh","https://github.com/netty/netty/security/advisories/GHSA-3g8r-4pfx-jmfh"],"products":["netty:netty"],"source":"nvd","synced_at":"2026-10-19T22:46:40.600842820+00:00"},"epss":{"cve":"CVE-2026-59920","score":0.00415,"percentile":0.35884,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-3g8r-4pfx-jmfh","url":"https://osv.dev/vulnerability/GHSA-3g8r-4pfx-jmfh","summary":"Netty: STOMP CONNECT Frame Header Injection in Netty","modified":"2026-09-10T03:51:10.205072585Z","packages":[{"ecosystem":"Maven","name":"io.netty:netty-codec-stomp","purl":"pkg:maven/io.netty/netty-codec-stomp","ranges":[">=4.2.0.Final <4.2.16.Final"],"fixed":["4.2.16.Final"]},{"ecosystem":"Maven","name":"io.netty:netty-codec-stomp","purl":"pkg:maven/io.netty/netty-codec-stomp","ranges":["<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."]}