Vulnerability · Published Jul 29, 2026 · Assigned by GitHub_M
CVE-2026-59920Netty: STOMP CONNECT Frame Header Injection
Medium 6.5
In plain English
A medium-severity security flaw in netty from netty. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 36% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | netty | no fix listed | DEBIAN-CVE-2026-59920 |
| Debian:13 | netty | no fix listed | DEBIAN-CVE-2026-59920 |
| Debian:14 | netty | no fix listed | DEBIAN-CVE-2026-59920 |
| Maven | io.netty:netty-codec-stomp | 4.2.16.Final | GHSA-3g8r-4pfx-jmfh |
| Maven | io.netty:netty-codec-stomp | 4.1.136.Final | GHSA-3g8r-4pfx-jmfh |
| Ubuntu:26.10 | netty | no fix listed | UBUNTU-CVE-2026-59920 |
Affected products (as reported)
Weakness: CWE-93 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
References
- https://github.com/netty/netty/security/advisories/GHSA-3g8r-4pfx-jmfh x_refsource_CONFIRM