CVE-2026-28368: Undertow is Vulnerable to HTTP Request/Response Smuggling
(updated )
A flaw was found in Undertow. This vulnerability allows a remote attacker to construct specially crafted requests where header names are parsed differently by Undertow compared to upstream proxies. This discrepancy in header interpretation can be exploited to launch request smuggling attacks, potentially bypassing security controls and accessing unauthorized resources.
References
- access.redhat.com/errata/RHSA-2026:25125
- access.redhat.com/errata/RHSA-2026:25126
- access.redhat.com/security/cve/CVE-2026-28368
- bugzilla.redhat.com/show_bug.cgi?id=2443261
- github.com/advisories/GHSA-8v4x-mgvp-p658
- github.com/undertow-io/undertow/commit/3ece0bf2b2cf5e01db8ca25e41b831e66d3f5961
- github.com/undertow-io/undertow/commit/904e26f1be62fb00b440538608a9574839821878
- github.com/undertow-io/undertow/commit/c5dc41479e9c3576552d7e98e31bb1c237ae155e
- nvd.nist.gov/vuln/detail/CVE-2026-28368
Code Behaviors & Features
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