Authentication bypass via raw STOMP header newlines
Published Jul 29, 2026 · Updated Jul 29, 2026
Header injection in Netty before 4.1.136.Final and 4.2.0 through 4.2.15.Final allows remote authenticated users to alter STOMP headers. StompSubframeEncoder writes raw newline characters from CONNECT and CONNECTED header values to the wire without validation, so brokers parse injected text as separate headers. Exploitation requires codec-stomp, attacker-controlled header input, no application sanitization, and a broker that honors the injected header; authentication bypass or privilege escalation is broker-dependent.
Summary
What happened
Header injection in Netty before 4.1.136.Final and 4.2.0 through 4.2.15.Final allows remote authenticated users to alter STOMP headers. StompSubframeEncoder writes raw newline characters from CONNECT and CONNECTED header values to the wire without validation, so brokers parse injected text as separate headers. Exploitation requires codec-stomp, attacker-controlled header input, no application sanitization, and a broker that honors the injected header; authentication bypass or privilege escalation is broker-dependent.
The record
- CVE
- CVE-2026-59920
- Published
- Jul 29, 2026
- Updated
- Jul 29, 2026
- Vendor
- The Netty Project
- Product
- Netty
- Classifications
- CWE-93, T1068
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 29, 2026CVE publishedPublication date reported by the CVE source.
- Jul 29, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 4.1.136.Final
- Affected versionversion=>= 4.2.0.Final, < 4.2.16.Final
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- STOMP CONNECT Header Injection PoCproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
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