Undertow: undertow: request smuggling via inconsistent header parsing
Summary
| CVE | CVE-2026-28368 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-03-27 17:16:27 UTC |
| Updated | 2026-03-31 18:20:30 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v3.1 9.1 CRITICAL from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS: 0.000820000 probability, percentile 0.241260000 (date 2026-04-01)
Problem Types: CWE-444 | CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 9.1 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
| 3.1 | [email protected] | Secondary | 8.7 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N |
| 3.1 | CNA | CVSS | 8.7 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Redhat | Build Of Apache Camel - Hawtio | 4.0 | All | All | All |
| Application | Redhat | Build Of Apache Camel For Spring Boot | 4.0 | All | All | All |
| Application | Redhat | Data Grid | 8.0 | All | All | All |
| Operating System | Redhat | Enterprise Linux | 9.0 | All | All | All |
| Application | Redhat | Fuse | 7.0.0 | All | All | All |
| Application | Redhat | Jboss Enterprise Application Platform | 7.0.0 | All | All | All |
| Application | Redhat | Jboss Enterprise Application Platform | 8.0.0 | All | All | All |
| Application | Redhat | Jboss Enterprise Application Platform Expansion Pack | - | All | All | All |
| Application | Redhat | Process Automation | 7.0 | All | All | All |
| Application | Redhat | Single Sign-on | 7.0 | All | All | All |
| Application | Redhat | Undertow | - | All | All | All |
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| bugzilla.redhat.com/show_bug.cgi | [email protected] | bugzilla.redhat.com | Issue Tracking, Vendor Advisory |
| access.redhat.com/security/cve/CVE-2026-28368 | [email protected] | access.redhat.com | Vendor Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-02-27T04:39:57.578Z | Reported to Red Hat. |
| CNA | 2025-08-27T00:00:00.000Z | Made public. |
Workarounds
CNA: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
There are currently no legacy QID mappings associated with this CVE.