CVE-2026-12606: CWE-444: Inconsistent Interpretation of HTTP Requests in Eclipse Foundation Eclipse GlassFish
Eclipse Grizzly in versions before 5.0.2, cannot properly parse the trailer section in malformed trailer header's line, which can be leveraged to perform HTTP request smuggling. Grizzly 5.0.1 supports system properties that enable the behavior that fixes the vulnerability - set org.glassfish.grizzly.http.STRICT_HEADER_NAME_VALIDATION_RFC_9110 and org.glassfish.grizzly.http.STRICT_HEADER_VALUE_VALIDATION_RFC_9110 system properties to "true".
AI Analysis
Technical Summary
CVE-2026-12606 is a medium severity vulnerability (CVSS 6.3) affecting Eclipse GlassFish versions 4.0.0 and 5.0.0. The root cause is that Eclipse Grizzly, the HTTP framework used, does not correctly parse malformed trailer headers, leading to inconsistent HTTP request interpretation. This flaw can be leveraged for HTTP request smuggling attacks. Grizzly 5.0.1 supports system properties (org.glassfish.grizzly.http.STRICT_HEADER_NAME_VALIDATION_RFC_9110 and org.glassfish.grizzly.http.STRICT_HEADER_VALUE_VALIDATION_RFC_9110) which, when set to "true", enable stricter validation that addresses the vulnerability. No official patch or remediation level has been published yet.
Potential Impact
Successful exploitation allows an attacker to perform HTTP request smuggling by exploiting inconsistent parsing of malformed trailer headers. This can lead to bypassing security controls, request/response desynchronization, and potentially unauthorized access or manipulation of HTTP traffic. There are no known exploits in the wild at this time.
Mitigation Recommendations
No official patch or fix has been published yet. Users of Eclipse GlassFish versions 4.0.0 and 5.0.0 should consider upgrading to Grizzly 5.0.1 or later and enable the system properties org.glassfish.grizzly.http.STRICT_HEADER_NAME_VALIDATION_RFC_9110 and org.glassfish.grizzly.http.STRICT_HEADER_VALUE_VALIDATION_RFC_9110 by setting them to "true" to enforce stricter header validation and mitigate the vulnerability. Monitor vendor advisories for official patches or updates.
CVE-2026-12606: CWE-444: Inconsistent Interpretation of HTTP Requests in Eclipse Foundation Eclipse GlassFish
Description
Eclipse Grizzly in versions before 5.0.2, cannot properly parse the trailer section in malformed trailer header's line, which can be leveraged to perform HTTP request smuggling. Grizzly 5.0.1 supports system properties that enable the behavior that fixes the vulnerability - set org.glassfish.grizzly.http.STRICT_HEADER_NAME_VALIDATION_RFC_9110 and org.glassfish.grizzly.http.STRICT_HEADER_VALUE_VALIDATION_RFC_9110 system properties to "true".
CVSS v4.0
Score 6.3medium
Affected software
pkg:maven/org.eclipse.glassfish/glassfishRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-12606 is a medium severity vulnerability (CVSS 6.3) affecting Eclipse GlassFish versions 4.0.0 and 5.0.0. The root cause is that Eclipse Grizzly, the HTTP framework used, does not correctly parse malformed trailer headers, leading to inconsistent HTTP request interpretation. This flaw can be leveraged for HTTP request smuggling attacks. Grizzly 5.0.1 supports system properties (org.glassfish.grizzly.http.STRICT_HEADER_NAME_VALIDATION_RFC_9110 and org.glassfish.grizzly.http.STRICT_HEADER_VALUE_VALIDATION_RFC_9110) which, when set to "true", enable stricter validation that addresses the vulnerability. No official patch or remediation level has been published yet.
Potential Impact
Successful exploitation allows an attacker to perform HTTP request smuggling by exploiting inconsistent parsing of malformed trailer headers. This can lead to bypassing security controls, request/response desynchronization, and potentially unauthorized access or manipulation of HTTP traffic. There are no known exploits in the wild at this time.
Mitigation Recommendations
No official patch or fix has been published yet. Users of Eclipse GlassFish versions 4.0.0 and 5.0.0 should consider upgrading to Grizzly 5.0.1 or later and enable the system properties org.glassfish.grizzly.http.STRICT_HEADER_NAME_VALIDATION_RFC_9110 and org.glassfish.grizzly.http.STRICT_HEADER_VALUE_VALIDATION_RFC_9110 by setting them to "true" to enforce stricter header validation and mitigate the vulnerability. Monitor vendor advisories for official patches or updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- eclipse
- Date Reserved
- 2026-06-18T11:27:18.643Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a55feea68715ace432dfb76
Added to database: 07/14/2026, 09:18:34 UTC
Last enriched: 07/30/2026, 01:36:15 UTC
Last updated: 08/26/2026, 22:52:08 UTC
Views: 61
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