Executive brief
Eclipse Grizzly, a networking framework used in the GlassFish application server, contains a flaw in how it handles specific web traffic headers. An attacker can exploit this to 'smuggle' hidden requests past security filters, potentially bypassing access controls or interfering with other users' sessions. This could lead to unauthorized actions or data manipulation within applications hosted on the affected server.
Technical details
A vulnerability exists in Eclipse Grizzly (and by extension Eclipse GlassFish) due to improper parsing of the HTTP trailer section. Specifically, the framework fails to correctly handle malformed lines within the trailer header, leading to an inconsistent interpretation of HTTP requests between front-end proxies and the back-end Grizzly server (CWE-444). A remote, unauthenticated attacker can exploit this by sending specially crafted HTTP requests to perform request smuggling. This can result in security bypasses or unauthorized request execution. The issue is resolved in version 5.0.2.
Affected products
- Eclipse Foundation Grizzly 4.0.0 to 4.0.2, 5.0.0 to 5.0.1
- Eclipse Foundation GlassFish 4.0.0 to 4.0.2, 5.0.0 to 5.0.1
Timeline
- 2026-07-14: advisory
- 2026-07-14: disclosed